E² (episode)
An accident during an attempt to use a Xindi subspace corridor places the Enterprise in a bizarre confrontation… with itself.

Summary

Teaser 
An elderly Vulcan woman is seated in her chambers meditating. Her son Lorian enters and grimly announces that they were unable to prevent the Xindi weapon probe from entering the vortex and that it is now on its way to Earth. Lorian notes that everything is happening as before. The elder woman is T'Pol, and replies that he now has no choice. He must find Jonathan Archer.

Act One 
On board the , Tucker enters T'Pol's quarters and requests neuro-pressure due to his stress and insomnia. A stricken look crosses T'Pol's face and she turns away asking that they break off the sessions. Tucker confesses he is not there for neuropressure and that he was worried about T'Pol's withdrawn behavior. T'Pol asserts that she is fine – and Tucker's resigned expression reveals he knows this is false but that she doesn't want to open up to him.

Enterprise is approaching the Kovaalan nebula containing a subspace corridor that will take it to its rendezvous with Degra near the Xindi Council planet. Degra warned that there were 1 or 2 Kovaalan ships in the nebula and that they were hostile. However, upon arriving, sensors indicate his information was out of date, as there are at least a half a dozen ships in the nebula. Archer orders measures to avoid detection for as long as possible, including using a Metreon cloud to hide their signature. Reed is optimistic that with luck they may be able to reach the corridor before they are confronted.

Degra's ship is docked with a Xindi-Primate starship for a meeting between three councilors. Degra's Xindi-Primate colleague on the Xindi Council is furious that he has told the Humans the location of the council's meeting place. Degra responds that the Enterprise was heavily damaged and could easily be destroyed by a single Xindi ship. He brushes aside rumors of other Earth vessels in the expanse. The three Xindi councilors debate the wisdom of allowing Archer to address the council. Jannar admits that Archer's evidence is difficult to explain. Degra asserts that the meeting is worth the risks, since if what Archer is saying is true, then all the council's work will have been for nothing. They will have to defend the Enterprise from the reptilians when they arrive for the meeting.

Enterprise drops out of warp near the nebula and T'Pol announces that an  starship is on an intercept course. Reed surmises the ship is , however the ship has the same markings as Enterprise and its commander is a man named Lorian who promptly requests that Archer reverse his course. A startled Archer complies and meets with the captain and his executive officer.

Lorian recounts the history of his crew. After entering the nebula, Enterprise was immediately ambushed. Enterprise escaped the Kovaalan ships by reaching the subspace corridor. However, her impulse manifold created a particle wake that destabilized the corridor and created a shift in time, causing them to emerge in 2037. Archer decided that Enterprise couldn't return to Earth, or they would contaminate their own history. T'Pol determined that return via the corridor was not possible. Archer resolved to wait until the time that they could either warn Earth or prevent the launching of the probe. To do this, Enterprise became a generational ship forming alliances with other species and gaining fuel, provisions and technology to survive. Lorian addresses a startled T'Pol as "mother".

Lorian advises Archer that he can avoid the disaster by not entering the corridor and instead enhance the plasma injectors using technology gained from Haradin traders. Lorian could not perform the modifications on his Enterprise because of the deterioration of his injectors. However with new injectors and structural modifications to Archer's ship, Lorian's calculations are that Archer's Enterprise will be able to achieve warp 6.9 for short periods – long enough for it to make the rendezvous with Degra in time.

Archer decides to trust Lorian after Phlox confirms via DNA matches that the executive officer, Karyn Archer, is Archer's great granddaughter, and that Lorian is in fact the son of Tucker and T'Pol. Phlox had discovered a way to combine the Vulcan and Human genomes.

Act Two 

Tucker sees features of his father in Lorian, as well as a Human sense of humor. The two quickly develop a bond of respect and when Tucker learns that he will die when Lorian is 14, he expresses his regret for not being around for him. Lorian confides to Tucker that he was a good father and is sure that he would have given him hands-on engineering experience, as opposed to having to read his logs to acquire the technical knowledge.

Karyn Archer gives her great-grandfather a tour of her ship, and he takes note of the doubling of efficiency of the atmospheric processors, the aliens aboard ship, old women, Denobulan children playing. Karyn explains that many of their crew are descendants of Phlox, who fathered nine children with Amanda Cole. She tells the captain her own great-grandmother was an Ikaaran named Esilia whose ship Enterprise rescued from an anomaly, and who Archer married. Archer observes that the existence of the future Enterprise would explain why the Xindi kept asking during his interrogation for the number of Earth ships in the expanse. Karyn confirms that they were likely scanned multiple times by Xindi ships.

Archer is taken to the elder T'Pol's quarters where it is evident from her warm embrace that she has learned to express her emotions. At an age of around 182 years, she is the only remaining original crew member. She inquires about Trip but declines Archer's offer to send him for a visit, knowing that such a meeting with her husband would be awkward. She regrets that there is no time to become reacquainted and hands to Archer a PADD that will prove that Lorian's plan could result in the destruction of Enterprise.

Discussing their future relationships in the mess hall, Hoshi tells Mayweather she had two children, Toru and a girl named Yoshiko, but has declined to discover who would be her husband. Mayweather says he married Corporal McKenzie, who he's only spoken with once so far. Reed joins them and Hoshi asks him who he ended up with on the other Enterprise. Reed uncomfortably mentions that he never married, while Hoshi notes there were bound to be some bachelors as women comprise only a third of the crew. Sensing Reed's uneasiness, Mayweather and Hoshi excuse themselves. After they leave, Reed sees a female crewmember looking for a seat. Fearing he might one day end up alone as he did in the alternate timeline, and he quickly invites her to take a seat.

T'Pol advises Archer that she and Tucker agree with the elder T'Pol's assessment that Lorian's modifications could overload the injectors and destroy the ship. Elder T'Pol has an alternate plan to modify the impulse manifolds so the corridor will not be displaced. Archer confronts Lorian about the risk of injector overload who claims the risk is only 22%. Archer is infuriated that Lorian withheld critical information regarding the risks and alternatives. Lorian is emphatic that Enterprise will be thrown back in time again but Archer retorts that he has two T'Pols who disagree, and flatly states the matter is not open for debate. It is his mission and his decision – Archer will proceed into the subspace corridor with modified impulse manifolds, and requests the assistance of Lorian's engineers to speed the work.

Lorian enters the quarters of elder T'Pol and berates her for warning Archer, believing that he is doomed to repeat the same mistake. T'Pol suggests to Lorian that his judgment is being clouded by the strong motivation of Human guilt he feels after failing to stop the Xindi probe. Lorian accuses T'Pol of not feeling the kind of urgency she would feel if Vulcan were threatened.

Lorian next meets with Karyn Archer and his tactical officer Greer to outline his plan to steal the plasma injectors, proceed at warp 6.9 so that he can meet Degra and the council in Archer's place. In response to his first officer's complaint that Archer's ship will be unable to go to warp, Lorian claims that his father will be able to fabricate new plasma injectors.

Act Three 
Tucker is working with the younger T'Pol on the modifications, states that their hundred-year old son is a "good kid," and relates to her the romantic events that would transpire between the two of them. T'Pol responds with apparent disinterest to the story of how Tucker would fill cargo bay 3 with sand and manufacture them a palm tree for their honeymoon. She puts up a good front as she rationalizes that acts of their counterparts don't necessarily imply they will do the same. Yet she is visibly irritated when he points out that she simply doesn't want to admit that under the right circumstances that she could have feelings for him. She states ruefully that she should never have experimented sexually with Tucker because she should have known that he would be unable to participate without also developing an emotional attachment. Tucker doesn't buy her evasion, and sarcastically insinuates that she is not truly in as much control as she wants him to believe. 

Lorian takes over engineering, and is preparing to remove the plasma injectors from the injector assembly. Before Greer can reroute the plasma, Tucker discovers them. He incredulously asks if Lorian realizes they will be helpless without the injectors and attempts to assert his influence as his father. Lorian listens, but then apologizes and fires a phase-pistol burst, stunning Tucker.

On the bridge, Archer is informed that the warp engines are disabled and that the plasma injectors are disengaged. Engineering doesn't respond and Lorian's Enterprise undocks, refusing responses to hails. As the ship prepare to go to warp, Archer orders Reed to disable their engines. The starboard nacelle is damaged preventing warp, and Lorian orders retreat at full impulse and for Greer to return fire. Archer orders T'Pol to the transporter room. Enterprise is hit again, losing hull plating and weapons, but Mayweather brings Enterprise close enough for T'Pol to transport an EPS manifold off of Lorian's ship. Archer orders T'Pol to next take the primary relays from C-Deck, after which Lorian's ship loses all power. Archer hails Lorian suggesting that each has some things that belong to the other.

Reed warns Archer that Lorian has a torpedo locked onto their starboard engine, and Archer emphasizes to Lorian how many people would be hurt if he pulls the trigger. Karyn Archer persuades her captain that the action is over with, emphasizing that these people are family and that she won't let him continue. Lorian reluctantly orders a stand down of weapons.

Act Four 
Later in the brig, Lorian is informed by Archer that he was lucky and that all injuries on both ships were minor. Archer's ship was almost crippled, and his mission would have been over. Lorian is unrepentant, repeating his assertion that Archer's mission is already over and that his course is the only logical one that has a chance of success. Lorian then reveals the guilt that has been driving him. He feels he is responsible for the death of the 7 million because he did not exhaust all options to stop the probe. He believes he could have rammed the probe but hesitated because it would mean the death of his crew. He blamed himself for allowing his emotions take over and prevent him from giving the order. Archer sees Lorian's determination and dedication to the mission and tells Lorian that with or without him, he is taking his ship into the corridor. Archer tells Lorian that the mission has a stronger chance of success if he agrees to work together with him, and decides to free Lorian and allow him to make the choice.

The two T'Pols meet in the elder's quarters. Elder T'Pol offers some advice about both isomagnetic collectors and emotions. Young T'Pol was unable to achieve more than 86% reduction of the particle wake with the impulse manifold modifications. The elder shows where to place an isomagnetic collector (a piece of Ikaaran technology the younger T'Pol was unfamiliar with) to reduce any residual particles, and gives T'Pol the schematics for it. While looking for the schematics, the elder T'Pol inquires whether she is feeling better after the effects of her Trellium withdrawal, warning that she will never fully recover from the effects and that the emotions she accessed will be with her the rest of her life. Young T'Pol looks stricken and wanders across the room to her tea. The elder advises her that there is someone on board Enterprise who can assist her. In a dazed manner, the young T'Pol responds that Phlox has already given her a neural suppressant. The elder shakes her head that she must reach out to Trip. Young T'Pol is at once revolted, fearful and relieved to hear confirmation of what she has suspected about her emotions for Tucker. The elder assures her that she cannot imagine what life would have been like without Tucker and that she should follow her heart.

Enterprise approaches the nebula. Upon entering, Reed detects three Kovaalan ships on an intercept course that immediately begin firing. The nebula interferes with targeting scanners and Reed is unable to return fire. After achieving a lock, Archer hails Lorian. Lorian's ship that had been hiding under Enterprise emerges from what appeared to the Kovaalans to be a sensor reflection. Both Enterprises attack and disable the lead ship. The other two retreat. But Enterprise cannot move having lost one of her primary drive coils in the attack. Before the Kovaalans can regroup, Lorian uses his tractor beams to take Archer's Enterprise in tow. But the Kovaalans return with four ships and target the towed Enterprises aft plating. Aft plating fails and weapons go offline. Lorian releases the damaged Enterprise to coast into the corridor while he turns his ship to protect Archer's. He promises to follow shortly. As Archer's Enterprise reaches the safety of the corridor, Lorian's ship suffers multiple hits as its phase cannons and torpedoes blaze against the attacking ships.

Enterprise emerges from the corridor in the correct location in the correct century with no sign of pursuit. They wait five hours for Lorian, but his ship never emerges. T'Pol states that it is unlikely they survived. Archer theorizes that perhaps by going through the corridor they fixed the mistake of the original Enterprise going back in time, therefore causing it to be removed from the timeline. T'Pol points out that if that were true, then they would not remember the other Enterprise.

A ship drops out of warp near Enterprise and interrupts further consideration of the fate of the other Enterprise. It's Degra's ship, ready to escort Archer to meet with the Xindi Council. Degra remarks that Archer is early.

Memorable quotes 
"The probe?"
"We couldn't stop it from entering the vortex. It's on its way to Earth."
"Seven million people."
"Everything is happening as it did before."
"Then you have no choice – you must find Jonathan Archer."
 - old T'Pol and Lorian

"Would you tell me what the hell is going on?"
 - Captain Archer, to Lorian

"You've hardly changed, Mother."
 - Lorian, to young T'Pol

"It's the strangest thing. I, uh… I look at you, and I see my father – right here, around the eyes. Now, the ears, those… those are your mother's."
 - Tucker, to Lorian

"You were a good father… strange, being able to tell you that."
 - Lorian, to Tucker

"Hello, Jonathan."
 - old T'Pol, to Captain Archer

"Who's the father?"
"I don't know. It was probably in their database, but I didn't look it up."
"Why not? You've got to be curious."
"Some things are better left a mystery."
 - Mayweather and Sato, discussing the identity of the father of her future children, Toru and Yoshiko

"There's no alternative. You'll be thrown into the past if you try to use the corridor."
"I've got two T'Pol's who disagree with you."
 - Lorian and Archer

"Only in the Expanse could I have a son who's nearly three times my age."
 - Tucker, to young T'Pol

"You're obviously unable to have a physical relationship without developing an emotional attachment."
"You know, all the other women on board must've been taken, 'cause I can't imagine any other reason why I would've married someone as stubborn as you. I'll go help Rostov with the port manifold. [Sarcastically] You seem to have everything under control."
 - T'Pol and Tucker

"I'm sorry."
 - Lorian, to Tucker, just before he shoots his father

"We can't do this."
"There's too much at stake."
"These people are family. I'm not going to let you kill them. Captain, it's over."
 - Karyn Archer and Lorian

"Attacking your ancestors doesn't sound very logical to me."
 - Archer, to Lorian

"Years ago, I… I swore to my captain on his deathbed… I'd save those seven million lives. You were the man I made that promise to."
 - Lorian, to Archer

"You'll never fully recover. The emotions you've accessed will be with you the rest of your life."
 - T'Pol, to her younger self

"If Enterprise hadn't been stranded in the past, it's possible I never would have married Trip. But I can't imagine what my life would have been like without him."
 - T'Pol, to her younger self

"They must've been surprised when your reflection turned and attacked them."
 - Lorian, to Archer

"Are you suggesting that the other Enterprise never existed? If you're right… then why would we remember them?"
 - young T'Pol, to Archer

"Captain, you're early."
 - Degra, to Archer at the rendezvous point (last line of the episode)

Log entries 
"Captain's Starlog, supplemental. I've decided to proceed with Lorian's plan to modify our warp engines. Both ships have moved a safe distance from the nebula to avoid conflict with the Kovaalans."
"Captain's Starlog, supplemental. It's been five hours, and the other Enterprise still hasn't arrived. Repairs to our impulse drive are underway."

Deleted scenes

Scene 22 
An expanded scene about the first talk between Tucker and Lorian about his paternity. Right after Lorian said that is strange being able to tell Tucker that he was a good father, the commander asks more about his mother, how he and T'Pol got together. Lorian says that she never told it to him, actually, and that she rarely talked about her husband, probably because it was too painful to her, as she cared for him a great deal. Tucker doesn't believe that they are talking about the same woman. Lorian tells that their relationship was somewhat contentious, but they were always affectionate towards each other. Tucker laughs and still can't see himself married with T'Pol, and starts to talk about if he and she were marooned on a desert island, perhaps it would be possible. Lorian interrupts him and suggests they finish up with these injectors.

Scene B33 
Captain Archer enters his Enterprises sickbay and encounters Phlox packing some things. The doctor says that sickbay in the alternate Enterprise is in poor shape and they are short on critical medical supplies, and asks the captain's permission to help them, to which Archer agrees. Phlox can't believe that his Rigelian parrot is still alive; he knew they had long lifespans but not that long. The captain interrupts to ask about some inoculations that he mentioned; the doctor says that eight members of the alternate Enterprise crew are suffering from low-grade Neubilean fever, and he would like to vaccinate everyone on both ships. The alternate Enterprises physician is very inexperienced and he also would like some time to give him a refresher course in viral propagation. Archer agrees to that as well.

Dr. Phlox mentions how this situation is remarkable, discovering an extended family that they never knew existed. He is saying that because he learned that he has nearly thirty living descendants on the alternate Enterprise, and he is anxious to introduce them to his wives on Denobula. Archer supposes that when the Xindi Mission is over most of their crew will want to return to Earth. Phlox says that from what he has gathered his great-granddaughter would be more at home on a starship bridge. Archer says that it seems both he and his descendant are cut from the same cloth. Phlox wonders if perhaps Starfleet will consider allowing children on board starships one day, since Admiral Forrest did let him bring Porthos. Archer laughs and says that he can imagine the look on the admiral's face when he sees two Enterprises pulling into space dock, and asks Phlox to keep him updated, leaving the sickbay.

Background information 
 The squared representation in the episode's name (²) can be visually considered as half a character, making "E²" visually shorter than  by only half a character and the shortest episode title in Star Trek.
The original story pitched by writer/producer Mike Sussman was somewhat different from the aired episode. In Sussman's pitch, the starship  would have used Xindi subspace vortex technology to travel from Earth to the Delphic Expanse in order to aid Enterprise in its mission. But because of an incompatibility in respective technologies, Columbia would have arrived in the Expanse more than a century in the past and been marooned there. Archer and his crew would've thus encountered a one-hundred year old Columbia, operated by the descendants of its original crew. Sussman was asked to revise the story, making Enterprise travel into the past and thus having the crew meet themselves and their own descendants, much as the Defiant crew had done in . Sussman, a long-time Trekkie himself, pointed out the similarity in the stories to the show's executive producers but was overruled. Those in charge felt that the story for "E²" was sufficiently different, and that enough years had passed between the airing of the two shows to explore this theme again. (This information was provided by Mike Sussman)
According to episode writer Mike Sussman, the name "Lorian" was an homage to the Elvish forest Lórien found in J.R.R. Tolkien's novel Lord of the Rings: The Fellowship of the Ring.
The final draft of this episode's script was issued on .
The vest worn by Lorian in this episode is a reuse of the same vest often worn by Jake Sisko in the final seasons of .
T'Pol mentions "Humans and Vulcans have never been able to reproduce", implying there have been Human-Vulcan-couples in the past 90 years who've tried but not been able to produce offspring. Here, the Doctor Phlox in the past found a way of combining Vulcan and Human genomes, leading to the conception of a Human-Vulcan hybrid, Lorian. Phlox, or other physicians, will find a way to repeat this in the future, ultimately resulting in the birth of hybrids like Spock.
T'Pol and Tucker, who were married, albeit in an alternate timeline, have the first Human-Vulcan hybrid, Lorian. His ultimate fate remains unknown, be it dead, alive, or erased from history. Doctor Phlox' accomplishment foreshadows the events in , where the DNA from T'Pol and Tucker is used to create another or the actual "first" Human-Vulcan hybrid, Elizabeth.

Links and references

Guest Stars 
 Randy Oglesby as Degra
 Tucker Smallwood as Xindi-Primate Councilor
 Rick Worthy as Jannar
 Tess Lina as Karyn Archer
And
 David Andrews as "Lorian"

Co-Stars 
 Tom Schanley as Greer
 Steve Truitt as Crewman #1

Uncredited Co-Stars 
 David Moore as Denobulan boy
 Unknown performers as:
 Crewman #2
 Crewman #3
 Crewman #4
 Xindi-Primate officers
 Girl with Denobulan boy

Stand-ins 
 Tiffany Turner as body double for Jolene Blalock

References 
2037; 2063; access tube; addiction; ancestor; asteroid; atmosphere processors; bachelor; chamomile tea; ; chromosome; ; coil spanner; ; collision course; ; command; ; council chamber; cripple; debate; Degra; Degra's ship; Denobulan; descendant; dozen; Earth; emotion; engineering log; EPS manifold; Esilia; Esilia's ship; expression; extended family; family line; first officer; flux coupler; "follow your heart"; generational ship; genetic marker; genetic profile; genome; great-granddaughter; great-grandmother; hands-on training; Haradin; heart; honeymoon; hull plating; hull plating relay; Ikaaran; impulse drive; impulse manifold; impulse wake; injector assembly; insomnia; intercept course; intimate relationship; ionize; isomagnetic collector; joke; kilometer; Kovaalan; Kovaalan starship; lead ship; logic; marriage vows; ; mess hall; meter; metreon gas; nebula; neural suppressant; neuro-pressure; NX class; palm tree; phase cannon; Phlox's descendants; Phlox's nine children; plasma injector; power coupling; primary drive coil; primary relay; Reed family; reserve power; ; sand; schematics; science officer; security team; sensor ghost; sensor log; sexual relations; sexuality; specs; Starfleet; subspace corridor; start-up routine; structural integrity; subspace corridor; tactical alert; targeting scanner; time travel; torpedo tube; Toru; Toru and Yoshiko's father; tractor beam; tractor emitter; trader; transporter; trellium; trespasser; ; vortex; Vulcans; Vulcan (planet); Vulcan language; warp engine; warp reactor assembly; Xindi Council; Xindi cruiser; Xindi launch platform; Xindi probe; Xindi weapon; Xindi-Primate starship; Yoshiko

Unreferenced materials 
cloth; ; Denobula; inoculation; Rigelian parrot; Neubilean fever; refresher course; vaccination; viral propagation

External links 
 
 
 

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fr:E² (épisode)
ja:ENT:エンタープライズ2
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ENT episodes