Project Daedalus (episode)
When the Discovery crew infiltrates Section 31's headquarters, suspicions arise that the crew may have a traitor in their midst. Burnham tries to help Spock but her efforts don’t go as planned.

Summary

Teaser
A shuttlecraft lands in the hangar of the , containing Admiral Katrina Cornwell, who tells Captain Pike and First Officer Saru that she does not believe her shuttle was traced. Saru confirms scans were negative on their end as well, before welcoming the admiral aboard; Cornwell admits she would prefer it were under better circumstances. Cornwell confirms that she has looked into Pike's concerns about Section 31, but before going into them, she requests a private meeting with Spock. Pike informs Cornwell that Section 31 planned to torture Spock with technology unknown to the rest of Starfleet, which would likely have killed him, and believes that they ordered their agent  to sabotage Discoverys spore drive. Pike warns the admiral that it is not prudent to trust Section 31, no matter that she may think they are on the same side; Cornwell retorts that Pike has no idea what she's thinking, before demanding to know where Spock is.

In the medical lab, Cornwell begins a cerebral mapping procedure on Spock before beginning her questioning. She starts by asking him his rank, position and assignment; he responds that his rank is lieutenant, and he is a science officer aboard the . Cornwell asks if Spock intends to be truthful; he replies that he does. When asked if he recently left a psychiatric facility without permission, Spock replies that he did not, as he committed himself, and thus did not need permission to leave. Cornwell then asks if he murdered Starfleet personnel upon leaving the facility; Spock answers that he did not. She then asks if he killed them in self-defense, and again the answer is in the negative. Cornwell asks why he did kill them, to which Spock replies he has been "quite clear" that he did not kill anyone at all. Glancing at the readout, the cerebral monitor reads "non-deceptive": Spock is telling the truth.

Walking through the corridors of the ship, Burnham protests to Pike that Tyler is innocent, that he would not sabotage the spore drive, and that he was loyal to Starfleet. Pike counters that Tyler's loyalty is to Section 31, which has a different agenda than Starfleet as of late. Burnham asks to speak to Tyler, but Pike is adamant that there be no contact; despite her history with Tyler, the mission takes priority. Spock is the only one who has had direct contact with the Red Angel, and Pike needs Burnham to help him figure out who it is, and what it wants. When he asks if he can count on her, Burnham replies that he can, and that he can also count on her proving Tyler innocent.

Cornwell continues to question Spock on his escape from the psychiatric facility, asking why he chose to leave with violence at all. Spock responds that he performed what was colloquially referred to as the "Vulcan nerve pinch", which disabled people without doing permanent harm. Cornwell reminds him that he was in a psychiatric facility, and asked why he escaped at all. Spock admits that he had not believed the visions from the Red Angel were real, and began to question his sanity; once he concluded he was sane, remaining confined would have been "unproductive". Moving on to the Red Angel, the admiral asks why it chose Spock to receive its visions; Spock admits he does not know, and that he has asked himself that question many times. When asked what its visions mean, Spock begins to answer just as Burnham enters, saying that someone or something is going to bring an end to all sentient life, and clarifies that means everything: No Humans, no Vulcans, no Federation, all conscious life. Burnham states that she believes Spock, and knows for a fact he did not commit murder. Cornwell retorts that Burnham may simply defending Spock because she is his sister. "Not by blood," Spock quickly adds, leaving Burnham with a hurt expression.

Cornwell reviews the results of her questioning with the senior staff, showing that Spock is telling the truth, or at least believes he is telling the truth. Saru questions the admiral's doubt, asking if the test is accurate; Cornwell concedes that it is one hundred percent accurate, but then so was what she was about to show them: footage of Spock from the psychiatric facility in which he manhandles the staff and then shoots them dead with a phaser. "That's not the Spock I know," Pike says, convinced it must have been doctored. Cornwell replies that it came straight from Starfleet Psychiatric. However, she also reveals that the admirals who run Section 31 have not responded to her in weeks, and that Control, 31's threat assessment system, has stopped accepting her data input codes. When asked who would lock her out, Cornwell is certain it is Admiral Patar, a Vulcan logic extremist, whose fanaticism is "worrying" to her. When the red bursts first appeared, Patar began lobbying Starfleet Command to turn its decision-making processes over to Control. Saru deduces that if Cornwell brought her concerns to Starfleet Command, she risked inadvertently informing Patar, which is why she has come to Discovery in secret. Cornwell explains that Control is maintained within Section 31's forward operating base; they need to go there, arrest Patar, and reset the system to accept their input. Starfleet depends on Control for critical decisions; if it's in the hands of extremists like Patar, the entire Federation is in danger.

Cornwell accompanies Pike and Saru to the bridge; upon seeing her, Tilly begins stammering about not being a fugitive (though mentioning her "rebellious phase" in her youth) before Pike asks if she had something to report. Tilly confirms that she traced the transmissions Tyler sent to 74 mark 5.6, which made no sense, as there was nothing there but empty space and a penal colony abandoned over a century earlier. According to Cornwell, however, the colony is not abandoned – it is in fact Section 31 Headquarters. When asked of Tyler's whereabouts, Pike informs the admiral that he is confined to quarters, and instructs Tilly to decrypt his transmissions before ordering Detmer to set a course for Section 31 headquarters.

Act One 
In her quarters, Airiam reviews her memory files, beginning with one from her life before receiving cybernetic alterations, showing her with her husband Stephen. She then reviews her memories from aboard ship, deleting a number of random encounters, before reviewing one in the mess hall with Tilly, Detmer, and Joann Owosekun; Detmer laughingly remarks that she does not play kadis-kot with either Tilly or Airiam anymore because they have memorized every gambit in the game. Amused by this, Airiam saves the memory to her archive. Another memory she saves is a sparring match with Gen Rhys in the ship's gym, and an encounter with Burnham. At that moment, her door chimes, heralding Tilly, who remarks that Airiam had "better be saving every single moment" with her. Airiam jokes that those are usually the first to go. Tilly admits to being envious of Airiam's ability to save or delete her memories; if she could do it, she wouldn't recognize her own mother. Airiam warns that Tilly would not be as envious if she had to deal with the process every week, which she admits is "tedious". Tilly notes a vial of sand next to a picture of Airiam and Stephen, asking if it was from the same beach. Airiam explains that had been their last day together, but their shuttle crashed. Shaken for a moment by this, Airiam asks if Tilly needed her for something; Tilly asks for help with decrypting Tyler's messages. "My memories are not going anywhere," Airiam replies; she would be happy to help.

In engineering, Stamets is examining the spore drive, wondering aloud what could have caused the failure, and comments on Burnham and Spock's silence; he does not like to listen to himself talk when he has an "audience". Burnham tells him that she and Spock are thinking, to which Stamets tells her to "think louder". Turning back to her display, Burnham begins reviewing with Spock the appearances of the Red Angel and the signals. On two occasions, the signal was followed by the appearance of the Angel – the mission to the interstellar asteroid and the confrontation with the Ba'ul on Kaminar, but only the signal was detected when they traveled to Terralysium. Spock adds that when he saw the Angel as a child, there was no signal, nor when it shared its visions with him. He questions the apparent connection: Is the Angel using the signals, or the other way around? Burnham believes Spock's visions must have some clue of what it wants; Spock replies that he believes it meant to warn them, nothing more. He adds a Vulcan phrase meaning "you are tending a plant that is dead". Burnham retorts she knows what it means, but Spock tells her that translation was not the essence of understanding. When asked if he had a better suggestion, Spock heatedly replies that his priority is to understand why, of all sentient beings, the Angel chose to communicate with him, to which Burnham asks if he believes it wants something from him personally. The Angel showed Spock an apocalyptic future, but he is unable to logically reconcile how he is to prevent that future from happening. Burnham has a thought occur to her: The purpose of logic was to problem-solve in an uncertain environment, so perhaps some inspiration was required. Stamets speaks up and asks if they might find that inspiration elsewhere, as their "loud thinking" was actually distracting.

On the bridge, Airiam comments to Tilly that she could see how her decryption work was difficult; the key encryptions were continually changing. Tilly jokes that it was good that Airiam was "half robot"; Airiam corrects her, preferring "cybernetically augmented", a sentiment that Detmer concurs with. Tilly is not so sure, as Airiam does not seem to have "done anything", before she finally uncovers the first part of the encryption. As she works, however, the three blinking lights from the probe flash again in her eyes, causing her to not respond to Tilly's teasing about being "pretty smart". When she notices Tilly there, she apologizes for being "focused", and suggests Tilly return to her station while she works. Detmer reports that they will be dropping out of warp within ten minutes, so Pike asks for defense schematics of Section 31 Headquarters. Cornwell explains that it is heavily fortified on all sides. Owosekun and Saru are both stunned to see mines as part of its defenses, as the Federation does not use mines. When Cornwell points out the Federation didn't build them, Pike dismisses that as a "distinction without a difference". Cornwell reminds Pike that they were  by Klingon warships with cloaking devices. "Sometimes in war, the terrible choice is the only choice," she adds, by way of justification. Pike is outraged, saying that giving up the Federation's values in the name of security was to "lose the battle in advance", and asks Cornwell if she sidelined the Enterprise specifically because she knew he would remind her of that. Cornwell replies that the Enterprise sat out the war because she wanted the "best of Starfleet" to survive if they lost to the Klingons – Pike, and all he represented.

In Burnham and Tilly's quarters, Spock comments that unlike Tilly, whose side of the room was littered with her mementos, Burnham has "no individual expression whatsoever", calling it an accomplishment to be "uniquely mundane". Burnham replies that she prefers to express herself through her work, not her choice of decor. From one of the alcoves in the room, Burnham produces a three-dimensional chess board. Spock is (for a Vulcan) incredulous; he is attempting to ascertain why the Red Angel chose him to expose a threat to the entire galaxy, and Burnham's solution was to play chess. Burnham replies that Spock's inability to logically reconcile the Angel's visions caused him to question his ability to examine the world logically; what better way to return to logic than with the game that represents it? Spock considers it "arrogant" for Burnham to assert that his present manner of thinking needed fixing at all; Burnham jabs right back, saying it was arrogant for him to assert that it didn't. Spock grudgingly gives in.

Act Two 
Airiam reviews files from the 's database in the science lab when Security Chief Nhan enters, saying that Tilly had been looking for her, and asking what she was doing. Airiam replies that she was looking for something to aid in the decryption, as even with all the benefits of her augmentation, it did not have an infinite storage capacity. Airiam then asks about Nhan's species, the Barzan, and their cybernetics that allowed them to breathe the Earth-equivalent atmosphere on board most Federation starships; when Nhan asks why she wants to know, Airiam admits to curiosity. Returning to her work, the lights flash in Airiam's eyes again, and she abruptly returns to the bridge. Nhan follows her, suddenly suspicious.

As she enters the bridge, Tilly runs over to her, saying that whatever Airiam had done to start cracking the code before was no longer working, as it appeared the system knew they were trying to crack it and began to change its tactics – which was impossible, as it was an automated system, not artificial intelligence. Airiam asks Tilly to stand with her and not to move until they solve this mystery; Tilly is confused at first, but agrees. Detmer brings the ship out of warp, and the crew gets their first look at Section 31's fortress headquarters for themselves. Pike orders Bryce to open a channel and tell Section 31 that Starfleet's most wanted ship had arrived, just as Owosekun's scanners show all of the mines around the base are armed. Bryce reports no response; Cornwell suspects they are too busy planning the "welcome party". Pike asks if Cornwell could get them through the defenses; Cornwell assures him she wouldn't risk it otherwise. He offers the admiral the center seat, but she refuses; "my mission, your ship," is her reply. She gives Detmer a route to take through the minefield, and warns that shields will have to remain down, as the mines were attracted to them. Pike gives the order to lower shields and bring them closer to the field.

In her quarters, Burnham plays chess with Spock, asking if there was a logical reason to sacrifice his rook; Spock replies that perhaps he simply dislikes rooks. Burnham retorts that perhaps he is simply trying to lose, which Spock considers an odd supposition, as he is a willing participant in the game. As she takes the rook with one of her own, Burnham mentions that Sarek had taught her a more elegant strategy the first day she played. Spock says that there were other strategies that their father chose to ignore in his "single-mindedness", moving a pawn closer. Burnham comments that Sarek would be disappointed in his lack of effort. "I disappoint him, he disappoints me, the sun sets, a new day begins," Spock replies. Burnham comments that he is a philosopher now, to which Spock replies that she is Human, and cannot presume to know Sarek's mind. Looking back to the game, Burnham notes that logically, the next step would be for his knight to take her pawn; Spock again makes a move she considers erratic, finally leading her to ask what he was doing, as she was only trying to help him. Spock dismisses her efforts, as he does not feel he needs her help. Burnham reminds him that their captain felt otherwise, as Spock was the only person who has had contact with the Red Angel. Spock had said he did not understand why it chose him, so Burnham says that's where they need to start. When Spock mocks her belief that taking her pawn would lead to the solution, Burnham refuses to take what she sees as his "posturing" seriously, considering it out of character. Spock reminds her that they have not seen one another in years, and she had no foundation to judge his character. He dismisses her as being self-important and trying to take responsibility for things beyond her control, and mocks her beliefs of guilt over the war with the Klingons and the deaths of her parents, because children should know when a warfaring race would attack without warning, going on to mock her by saying that perhaps a child fighting Klingons would have made a difference. Burnham, enraged, snaps at him to shut up; Spock goes on, reminding her that she had been trapped behind a door and could not have stopped it, and it was unreasonable to believe otherwise. Yet she continues to do so, just as she believed she could save Spock and his family from the logic extremists when they were in fact were targeting him, the "half-Human abomination"; Burnham's presence in Sarek's house was beside the point. When Burnham fails to see the point he is making, Spock is blunt: Burnham avoids reality because it was easier to shoulder burdens than to face grief. Burnham is clearly disheartened, hoping she and Spock would have a new start. Spock replies that they will never be able to relate as equals so long as she continues to believe every burden is hers alone. In the spirit of honesty, Burnham snaps back that she wants Spock to stop taking out whatever is affecting him on her and identify what really angers him. Spock's voice rises as he says there was nothing to identify, that he was angry, pure and simple. When Burnham asks if it was because he felt he failed as a Vulcan, or as a Human, Spock is now shouting, saying that he felt failure to be "liberating", and that for the first time he enjoyed expressing emotion. He then smashes the chess table in a rage, before leaving a shaken Burnham in her quarters. At that moment, Pike's voice sounds over the intercom, calling her to the bridge; she gives a pained chuckle as she reports she is on her way.

On the bridge, Pike orders yellow alert, and tells Detmer to take them in. The crew is on edge just as Burnham enters, and Saru notices she appears distraught. Burnham is surprised at her first view of Section 31 Headquarters, with the most defensive weapons she had ever seen in one place. No one from Control was answering hails, and as it was a former prison, it would be built to prevent lifesign scans; Pike orders Burnham to find a workaround. Saru asks if Burnham was alright, to which she unconvincingly replies she was fine and goes to work. Pike then asks Tilly if she's decrypted the messages yet, to which she reports that she and Airiam are working as fast as they could. Rhys then reports a problem: blade mines, which could "slice through the hull like cheese". Saru adds that someone seems to be guiding them directly at Discovery, something Cornwell remarks should not be possible. As the mines begin slicing into the hull, Pike comments that it seems to be very possible, ordering red alert, shields up. Over the intercom, he warns the crew to "brace for a bumpy ride", and orders evasive maneuvers, pattern Lambda ten. At her station, the lights blink again in Airiam's eyes, and she tells Tilly to help the others, despite telling her earlier not to move until they broke the code. Airiam reassures her that she has the decryption handled, and tells her to go. Nhan continues to observe Airiam. Detmer is unable to shake the blade mines, as it seems whoever is controlling them is anticipating Discoverys moves; Pike orders her to switch to evasive pattern Gamma four. Cornwell is unable to shut down the mines, as they've been reprogrammed, so Pike tells Bryce to hail Starfleet Command and tell them to order Section 31 to stand down. As they continue to traverse the field, Detmer reports to her confusion that the sensors show the ship to be upside down, which Cornwell explains are the result of blackout mines, which confuse navigational sensors. The helm does not appear to be responding, but Cornwell adamantly insists it is, and that Detmer is flying blind, like at Starfleet Academy. Bryce reports no response from Starfleet. Detmer is desperate, saying she is trying her best, to which Pike says it was not good enough, that it wasn't a game. Thinking to her chess game with Spock, Burnham speculates that perhaps it is: If the mines are being controlled by computer, it would be able to anticipate the standard evasive patterns; what was needed to confuse it was "randomness and chaos". Pike tells Detmer to "trust her training", and calls on the crew to give random evasive patterns. At her station, Airiam appears to be downloading some kind of information, which then sends out a signal; as the signal sends, the mines suddenly deactivate and veer off.

The crew reports only five injuries, all of them in engineering; Detmer's damage report shows that warp drive and impulse drive are offline, as if they were specifically targeted. Bryce then reports that they are being hailed by Admiral Patar of Section 31. Pike cancels the red alert and orders a channel opened. Cornwell is indignant at Patar attacking a Federation starship, but Patar counters that as Discovery is a fugitive vessel harboring fugitive officers, she was deemed too dangerous to be allowed to approach Section 31 Headquarters. Pike believes Starfleet would have something to say about that, but Bryce reports no contact with Starfleet – because, Patar explains, the order to attack Discovery came from Starfleet Command.

Act Three 
Pike indignantly tells Patar that if Starfleet ordered an attack, they could tell him personally. Patar warns him not to escalate the situation further, and that a Section 31 vessel was en route to board them. When asked why, Patar smugly replies that Starfleet regulations were extremely specific on the definition of treason, and Pike, the Discovery, and Admiral Cornwell all applied. Cornwell retorts that if Section 31 thought they were coming to arrest her and the Discovery crew, they could think again. Patar says she believed Cornwell had "noble intentions" by going to Discovery, but by abandoning her duties to conduct a secret mission with fugitives, she became one herself. As a result, Patar coldly informs her, she no longer had the authority to choose her own fate, before the channel is abruptly closed. Cornwell insists that no matter the circumstance, they cannot abandon the mission: They had to board the station and reset Control. Pike asks if there was something about the look on his face that implied he'd changed his mind, much to the amusement of the crew; he orders Rhys to scan for further weapons on the base, and to call down to engineering to restore the spore drive. He tells Saru to form a landing party and meet him in the ready room; Saru insists he would be better remaining on board ship, at which point Pike then selects Burnham.

In engineering, Stamets continues to fruitlessly search for the cause of the spore drive failure, asking a power conduit aloud not to shock him. Working nearby, Spock wonders if Stamets realizes "inanimate infrastructure" couldn't hear him. As he examines the conduit, it shorts out, causing the power inside the engine room to fail. Spock tells him it makes his work impossible, and that he was not being hyperbolic when he said the future of the galaxy was at stake. Stamets suggests that if Spock wants to save the galaxy, he can start by helping Stamets restore power before Section 31 arrives to arrest them. Spock concedes he has a point. As they work, Stamets asks if Burnham's idea helped figure out why the Red Angel chose Spock; Spock admits he still did not know, considering himself an "illogical" choice despite all of the angles he had explored. Stamets asks if perhaps Spock had considered what made him unique; Spock admits he is half-Human, which is unusual, but there were others. Stamets explores a hypothesis: If he were the Red Angel, he'd choose who he would mind meld with carefully, not just any random Vulcan. He encourages Spock to keep trying, and he'd eventually figure it out. Just then, Spock repairs the conduit and restores power in engineering. Stamets comments that he wished the spore drive was that easy; he believes the problem with the drive is the navigator – himself – which he sarcastically dismisses as being "unimportant", as all he does is contain the map to the entire mycelial network. Spock points out that Stamets has traveled in the network hundreds of times, and would know how to travel between two points without assistance; perhaps Stamets simply does not have faith in his own abilities. Stamets suggests that whatever issue Spock had with Burnham, she risked her life to bring him to Discovery, and that she loved him. Making an observation of his own, Spock points out that he saw Dr. Culber moving out of their quarters, and that Stamets was upset at this; Stamets confirms this, saying that Culber needed distance. Spock submits that Stamets' assessment is inverted – that Culber needed distance not because he no longer had feelings for Stamets, but because he no longer knew how to feel about himself.

In the ready room, Burnham briefs Pike, Saru, and Cornwell on Section 31 Headquarters. Other than the data center where Control was located, power and life support were disabled all over the station, meaning the landing party would have to beam over in environmental suits. Nhan asks Cornwell if she knew how many guards were on site; Cornwell admits she has not been to the base since before the war, and that Nhan's guess was probably better than hers. Detmer is to keep the ship close enough to the base if at all possible, while Airiam would beam over to the data center once the landing party had secured it, in order to restore Cornwell's access to Control. Airiam volunteers to go aboard with the landing party first thing, just in case Control has any backup defenses; Nhan pledges to look after her. Pike wishes them luck, and sends them on their way. Burnham, Nhan, and Airiam beam onto the station, hovering for a moment above the deck before their gravity boots activate. Phasers in hand, they move ahead, Burnham reporting back to Discovery that artificial gravity was out and there were still no lifesigns. Checking in again to make sure Discovery was receiving the visual feed from the EV suits, Burnham spots floating objects in the corridors which she recognizes as globules of frozen blood. Burnham asks Nhan if she knows a way to restore life support; seemingly reluctant to let Airiam out of her sight, Nhan nonetheless moves off. Burnham tells Airiam to stay close. They find more blood and signs of a struggle, though no sign of against what or by who. As they enter the next corridor, they discover a body… and then look up to find three more. Nhan brings up the gravity and life support systems, and the frozen corpses collapse to the floor. Examining one body, Airiam's biometric scans show they died at least two weeks earlier. Turning one body over, Burnham is shocked to find herself staring at the frozen, dead face of Admiral Patar. Two other corpses, an Andorian and a Tellarite, are also Starfleet admirals. Pike is astonished: "If she's dead, who the hell was I talking to?" Saru believes he has an answer: As all living beings had a heat signature, he should have seen a change in Admiral Patar's when her authority was challenged, but did not… because the Admiral Patar they spoke to was a hologram. He then moves to the evidence of Spock "murdering" the staff at the psychiatric facility, and examines the footage in ultraviolet light. Again, there were no changes, despite the violent attack – it was also all holograms, intended to frame Spock for murder. Control had created the forgery, and then created the holographic Patar after it killed the real one and her cohorts. Pike realizes they were up against the system itself. Tilly, clearly looking distraught, examines the ship's data usage, and notes that Airiam's computer activity was incredibly high. Cornwell wonders: if Control was against them, trying to block them from contacting Starfleet, why would it allow a landing party aboard the station? Pike speculates that perhaps it wanted something from them; Tilly speaks up, saying that it wanted something from Airiam. Reviewing the data activity, Tilly realizes that Airiam transferred her entire memory archive into Discoverys computers; none of it was inside her head anymore, which leads Pike to wonder what she downloaded in its place. He orders Bryce to open a secure channel to Burnham and Nhan only, then asks Stamets for an update on the spore drive, as they might need it very soon; Stamets reports he will be ready when needed.

Hearing the doors banging together, Burnham draws her phaser and stands ready, looking relieved when Nhan forces the door open. It appeared that the admirals were trying to restore life support when at least one of them was cut in half by the door. Just then, they both receive the comm from Pike, who asks what Airiam is doing; Burnham replies she is uploading Admiral Cornwell's access to Control. Pike tells them that she's not, and orders them to stop her. As Airiam wheels on them, both Burnham and Nhan see the red lights flashing in her eyes, just as she raises her phaser and fires on them. Airiam reaches out and tears out one of Nhan's rebreather implants, causing her to begin choking on the air, before knocking her across the room, leaving Burnham to face her alone.

Act Four 
Even as Burnham tries to determine what was wrong, and Pike ordering her to stand down, Airiam attacks Burnham relentlessly, unshaken by any blow she receives in return. Driven to desperation, Burnham manages to gain the upper hand using Nhan's phaser rifle, before finally pushing her into the nearby airlock. Checking back in with Discovery, Pike reveals that something has taken control of Airiam through her augmentation. Tilly discovered that the transmissions to Section 31, supposedly from Tyler, were in fact from Airiam – and that she downloaded all of the Sphere's data on artificial intelligence, collected over more than a hundred thousand years. Burnham realizes this is what Control wanted – to evolve, to become sentient… and if it became a conscious lifeform, it would wipe out all life in the galaxy, exactly as the Red Angel had shown Spock. As she tries to delete what Airiam uploaded into Control, the door to the data center shuts, while Airiam tries to manually override the airlock. Unable to find a technical solution, Tilly asks for a channel to be opened to Airiam. She tearfully tries to reason with her and reach her emotions, transmitting Airiam's memory of herself with Tilly, Detmer, and Owosekun in the mess hall, and pleading with her to remember that she was a Starfleet officer, a good colleague, and a good friend, and to recognize Burnham as a friend and colleague. Airiam finally responds, sounding panicked, as she explains she is unable to stop what she is doing because Control is overriding her motor functions; she was only able to transmit 25% of the AI data, and Control needed her to finish. She tells Burnham to open the outer door of the airlock and vent her into space. Burnham is horrified, and refuses outright; as Stamets and Spock arrive on the bridge, Airiam warns that if she doesn't, she will unlock the inner door, kill Burnham, complete Control's mission, and then destroy Discovery, killing everyone onboard. Seeing no alternative, Pike orders Burnham to open the airlock. Spock tries to reason with Burnham that it's either her or Airiam, and Airiam herself tells her it's the only way, but Burnham is adamant that Airiam can be saved, and tries to blast through the door to the data center. Airiam reveals that Control wanted her to kill Burnham, and that "everything" was because of her. She asks Burnham to tell the crew she loved them, and that she had to find "Project Daedalus". Before she could ask what that was, the airlock opens, venting Airiam into space. Nhan, who was able to regain part of her rebreather implant, had triggered the airlock. Aboard Discovery, the crew stares in stunned silence; Burnham pounds the door in anguish, before breaking down in tears.

Outside, Airiam drifts away; in her last moment before her cybernetics suffer critical failure, she relives her favorite memory, the one Tilly transmitted to her just before the end: The memory of herself and Stephen before the shuttle crash, walking on the beach: "But we're coming home!"

Memorable quotes 
"Did you recently leave a psychiatric facility without permission?"
"No. I committed myself to the facility, therefore required no permission to leave it."
"When you left, did you murder Starfleet personnel in the process?"
"I did not."
"Did you kill them in self-defense?"
"I did not."
"Can you explain to me why you did kill them?"
"Admiral, I believe I've made myself with clear. I did not kill anyone at all."
- Katrina Cornwell and Spock

"You better be saving every single moment with me."
"Actually, those memories are always the first to go."
- Sylvia Tilly and Airiam, as Airiam goes through her memories

"Kind of lucky you get to delete everything you want to forget. If I could do that, I probably wouldn't recognize my mother."
"You'd be less envious if you had to go through the process each week. It can be tedious."
- Sylvia Tilly and Airiam

"Could one of you say something, please? I don't like to listen to myself talk when I have an audience."
"We're thinking, commander."
"Think louder."
 - Stamets and Burnham

"Good thing you're half robot."
"I prefer 'cybernetically augmented', thank you very much."
"Three cheers for cybernetics!"
 - Tilly, Airiam, and Detmer

"Admiral, wanna tell us what kind of shitstorm we're flying into?"
 - Pike, to Cornwell, as Discovery approaches Section 31 Headquarters

"You sat out the war because if we'd lost to the Klingons, we wanted the best of Starfleet to survive. And as this conversation makes clear, that was you… and all you represent."
"Thank you."
"You're welcome. Now, will you get off my ass so we can get back to work?"
 - Cornwell and Pike, on why the Enterprise was kept out of the war

"I am trying to understand why the Red Angel chose me to expose a threat to the entire Galaxy, and your solution is to play chess?"
"When the Red Angel showed you visions you couldn't reconcile, it caused you to question your ability to examine the world logically. What better way to return to logic than his the game that represents it?"
"It is arrogant of you to assert that my present manner of thinking requires fixing at all."
"It is arrogant of you to assert it doesn't. Or you're just afraid you'll lose."
"All right, Michael. Let's play chess."
 - Spock and Michael Burnham, before they play chess

"I think our father would be disappointed in your lack of effort, don't you?"
"I disappoint him, he disappoints me, the sun sets, a new day begins."
- Michael Burnham and Spock

"My perception of reality was challenged by visions of a time-traveling entity. Who should help me but you, of course, after all the entire Klingon War was your doing."
"No."
"Even your parent's death was your responsibility."
"Stop it."
"If only you hadn't asked to watch a star become supernova. But you're wise to blame yourself. Children should know when a warfaring race will attack without warning. Perhaps you could have done something. A child fighting a Klingon – those are excellent odds."
"SHUT UP!"
- Spock and Michael Burnham as their frustrations begin to boil over

"We will never relate as equals so long as you attempt to assume every burden as yours alone."
"Since we're being honest with each other, you need to stop taking whatever this is out on me! You need to identify why you're really angry!"
"There is nothing to identify. I am angry, pure and simple."
"Because you feel like you failed as a Vulcan, or as a Human?"
"What I feel is that failure is liberating! And for the first time, I enjoy expressing emotion!"
 - Spock and Burnham, pouring out their frustrations toward one another

"If Starfleet ordered an attack, they can damn well say it to my face."
- Christopher Pike, after Section 31 attacks Discovery

"Okay, come on. Please don't shock me."
"You do realize inanimate constructed infastructure cannot hear you."
"Really? You're kidding."
- Paul Stamets and Spock, as Stamets hopes a conduit doesn't shock him

"This makes my work impossible. And I am not being hyperbolic when I say the future of the galaxy is at stake."
"Well, uh… unless I can reroute power to the adjacent conduit, isolate the corruption, fix it and the spore drive, we're all gonna get arrested, so… if you want to save the galaxy, start by helping me."
"A fair point."
 - Spock and Stamets

"Airiam, what are you doing?!"
- Michael Burnham as Airiam turns on her and Nhan 

"Whatever this thing is making you do, this is not who you are. You are a- a Starfleet officer. You're an amazing colleague, and you are a great friend. And also like the best Kadis-kot player I've ever seen, and I should know. I won regionals when I was, like, ten. Airiam, this is not you. Please."
- Silvia Tilly, to Airiam, as Control takes over her body

Background information

Story and script 
 In the interim between the first and second seasons of ,  declared to DIS staff writers Erika Lippoldt and Bo Yeon Kim, "I want to see her story [….] I want to know what this character's about [….] What the hell is she? Where is she from? Like, all of that stuff. So, you have Season 2 to clear that up for me. That's just my request."

Cast 
 Wilson Cruz and Shazad Latif are not credited as main cast members and do not appear in this episode.

Production 
 Jonathan Frakes was originally hired to direct ; however, because of the delays in production due to the firing of showrunners Aaron Harberts and Gretchen J. Berg and the extension of the season from thirteen episodes to fourteen, he was assigned to direct this episode instead.

Music and sound 
 A couple of musical cues from this episode were released in the soundtrack collection Star Trek: Discovery - Season 2. These were "Airlock" and "Ariam in Space", which serve as the final two musical cues in the episode. However, the version of "Ariam in Space" features a piano rendition of the DIS end credits tune which isn't featured during the episode's end credits.

Continuity 
 This episode reveals that Admiral Patar, as well as the unnamed Andorian and Tellarite admirals seen in , had been dead for two weeks. Patar's appearance on Discoverys viewscreen is revealed to be a hologram created by the Section 31 artificial intelligence Control.
 The episode seems to canonize certain elements first revealed in the Discovery tie-in  The Way to the Stars by Una McCormack. Tilly briefly mentions how, at the age of sixteen, she underwent a rebellious phase and took part in activities such as computer hacking. This matches up with the events depicted in the novel, released two months prior to the episode's airing.

Reception 
  The fact that Jonathan Frakes would be directing a second episode of DIS Season 2 had been established in .

Production history 
 : Title publicly revealed 
 : Premiere airdate on CBS All Access
 : International release date (outside Canada and the USA)

Links and references

Starring 
 Sonequa Martin-Green as Michael Burnham
 Doug Jones as Saru
 Anthony Rapp as Paul Stamets
 Mary Wiseman as Sylvia Tilly
And
 Anson Mount as Christopher Pike

Guest starring 
 Jayne Brook as Katrina Cornwell
 Ethan Peck as Spock
 Rachael Ancheril as Nhan

Co-starring 
 Hannah Cheesman as Lt. Cmdr. Airiam
 Emily Coutts as Lt. Keyla Detmer
 Patrick Kwok-Choon as Lt. Gen Rhys
 Oyin Oladejo as Lt. Joann Owosekun
 Ronnie Rowe Jr. as Lt. R.A. Bryce
 Julianne Grossman as Discovery Computer
 Arista Arhin as Young Michael Burnham
 Alisen Down as a Starfleet Psychiatrist
 Tyler Hynes as Stephen
 Tara Nicodemo as Admiral Patar

Uncredited co-stars 
 Avaah Blackwell as Osnullus bridge officer
 Andrea Gallo as Discovery sciences crewmember
 Daniel Montlouis as Discovery operations crewmember
 John Mucciacito as Discovery engineer

Stunt doubles 
 Ieisha Auyeung as stunt double for Sonequa Martin-Green
 Joanne Leach as stunt double for Hannah Cheesman
 Julie St-Louis as stunt double for Rachael Ancheril

Stand-in 
 Stacy-Ann Buchanan as stand-in for Sonequa Martin-Green

References 
agent; albatross; aloha; airlock; artificial intelligence; asteroid; battle drill; Barzan; ; blackout mine; blade mine; ; blood; brain; brain scan; breather; cerebral mapping; Class C shuttlecraft; computer core; Control; ; cybernetics; cyborg; ; elopement; evasive maneuvers; ; fanaticism; frisbee; forward operating base; Hawaii; heart; hologram; Human; instinct; kadis-kot; Kaminar; kidney; life support system; liver; logic; logic extremist; lungs; memory; mine; murder; pawn; penal colony; ; Project Daedalus; radiation; red alert; Red Angel; red burst; regionals; robot; Rocklin; rook; sanity; Sarek; Section 31; Section 31 Headquarters; shields; Siobhan; source code; ; spore drive; Starbase 5; Starfleet Command; Starfleet Psychiatric; supernova; Terralysium; three-dimensional chess; torture; tracking; translation; treason; trust; ultraviolet radiation; vision; Vulcan; Vulcan language; Vulcan nerve pinch; worker bee; yellow alert

External links 
 
 
 

de:Projekt Daedalus (Episode)
es:Project Daedalus
fr:Project Daedalus (épisode)
pl:Project Daedalus
DIS episodes