No actor has appeared in all six Terminator films. Just one, Arnold Schwarzenegger, appeared in five. Only only other actor appeared in the first three Terminators with Schwarzenegger, and it’s not Linda Hamilton (who bailed after T2) or Michael Biehn (who technically only appeared in The Terminator, plus a cameo in a deleted scene from Terminator 2). Despite the fact that this man is almost completely overlooked in every history of The Terminator, he is maybe the franchise’s greatest character. He’s certainly the most relatable one. His name is Dr. Silberman — though audiences probably remember him as “that doctor guy” because he’s played by consummate That Guy actor Earl Boen.

Dr. Silberman fills a small but crucial role in 1984’s The Terminator, 1991’s Terminator 2: Judgment Day, and 2003’s Terminator 3: Rise of the Machines. While his appearances are brief, they collectively add up to a pretty compelling character arc. His role certainly exhibits more consistency and continuity than the franchise around him, which began to make less and less sense after Dr. Silberman disappearance from the series with Terminator Salvation in 2009. (This may not be a coincidence.)

He debuts in James Cameron’s The Terminator in the Los Angeles police station where both Hamilton’s Sarah Connor and Biehn’s Kyle Reese are being held after her rescue (and his arrest) following several violent skirmishes with Schwarzenegger’s killer cyborg. This is the same police station where Schwarzenegger delivers his immortal line “I’ll be back,” shortly before he drives a car through the building’s front window.

Although the Terminator goes on to kill almost every cop inside the station, Dr. Silberman survives. In a fluke of luck, he goes off-shift literally the moment Schwarzenegger arrives looking for Sarah Connor. Silberman’s pager goes off right as the Terminator enters the building, so he doesn’t even see the face of the robot whose existence will come to define his professional life for the next several decades.

The beat with Silberman narrowly escaping his own death is a wry bit of comedy by Cameron and co-writer Gale Anne Hurd, because Silberman is the only person in that police station the audience might actually want to see die at the hands of an Austrian killborg. Silberman is the criminal psychologist assigned to assess the mental state of Kyle Reese, who insists he is a soldier from a post-apocalyptic future who’s been sent back through time to protect the mother of his society’s great leader. It’s a laughable fantasy — except viewers knows Reese is telling the truth, having already seen both Reese and Terminator travel back through time to arrive in Los Angeles circa 1984.

Silberman didn’t personally witness any of that, though, and he is not convinced by Reese’s story. He yawns through parts of it. He checks his pager. In a meeting with Sarah Connor and several other cops after his interrogation, Silberman quips “In technical terminology, he’s a loon!”

From a writing standpoint, Silberman’s scene is ingenious, because it gracefully inserts tons of information about The Terminator’s dark future in a way that doesn’t feel overly expository. Placing the scene after the audience is convinced of Reese’s authenticity, but before Silberman is, and having Silberman dismiss everything Reese says makes him an instantly unlikable guy, even though he is asking all the questions a viewer would be asking in his situation. And then, having made us want to see this guy get his just deserts, letting him off the hook is the ultimate audience swerve.

That swerve proved fortuitous, as did Silberman’s prophetic line “I could make a career out of this guy!” When Cameron returned to The Terminator seven years later, he was able to bring Boen back to reprise his role and make good on Silberman’s promise. In Terminator 2: Judgment Day, Silberman works as Sarah Connor’s psychiatrist in the mental hospital where she is confined. With Reese dead and the remains of the first Terminator missing (they were taken by Cyberdyne Systems, where they are being experimented upon), Sarah now seems insane.

In T2, Silberman gets to once again play the role of the loathsome skeptic — and sneaky exposition deliverer. His character introduces Sarah Connor as part of a tour of the mental hospital, where he essentially explains the premise of The Terminator’s future for anyone who never saw the first film (or forgot its details after seven years) as part of a description of Sarah’s "delusional architecture.”

Silberman’s role is hugely important to the way T2 works, because Sarah Connor does seem slightly insane as the film begins. She’s angry. She’s disheveled. She’s fighting with her doctors and the hospital orderlies. She’s not the easiest character to identify with or root for, especially for viewers who might have missed the first Terminator. Boen’s drier than milquetoast persona, his offhanded contempt for his patient, makes us want to believe and trust Sarah, and justifies every ounce of rage she displays in T2’s early scenes.

Every sequence in Terminator 2’s first act builds towards a confrontation at Sarah’s mental hospital. She’s so poorly treated by the staff, from Silberman on down, that it’s difficult not to root for Robert Patrick’s liquid metal T-1000 to wipe out everyone in the place. Naturally, Cameron swerves the viewer again, denying them the pleasure of some sort of righteous vengeance. Sarah does break Silberman’s arm as she tries to escape, but when Schwarzenegger and Patrick’s robots show up, Sarah becomes understandably distracted and he emerges relatively unscathed. The last time we see him in the movie, the T-1000 runs past him without a second look while following the T-800 terminator, Sarah Connor, and her son John (Eddie Furlong) down an elevator shaft.

There’s one key difference between Silberman’s role in Terminator and T2. At the very end of that sequence, he witnesses something that isn’t so easy to dismiss as delusional architecture, when the T-1000 morphs around the bars of the hospital hallway. It’s literally the last moment Boen appears onscreen, so it would take another 12 years to find out how this impossible scenario — and the confirmation that everything Sarah Connor and Kyle Reese told him was true — affected him.

Dr. Silberman’s final appearance came in 2003’s Terminator 3: Rise of the Machines, when Boen played him for the final time (to date) in a brief sequence involving that film’s Sarah Connor figure, a veterinarian named Kate Brewster (Claire Danes). Kate has been kidnapped and dragged along for a wild adventure with a now-adult John Connor (Nick Stahl) and another Schwarzenegger Terminator. She escapes and is being treated in an ambulance when who should arrive but none other than Dr. Silberman, who now works as a “post-trauma counselor”:

Boen has just this one scene in T3, but he’s really terrific here, letting Silberman’s chipper facade melt away as Kate’s cries of “He’s really not human!” resonate with his own trauma. Director Jonathan Mostow doesn’t reveal exactly what Silberman’s been up to in the interim, but it seems clear he hasn’t turned into a true believer like Sarah Connor. He’s done his best to pretend the incident with the T-1000 was a figment of his imagination.

The emergence of the Terminator sends Silberman running for his life yet again, marking the third time he survives an encounter with a murderbot. The next Terminator film, Terminator Salvation, was set after the Judgment Day War, so there was no place for Silberman. And while the first attempt at a reboot, Terminator Genisys, recast a lot of existing characters from the franchise, it didn’t give us a new Dr. Silberman. (J.K. Simmons could have definitely played the character; he was cast instead in the role of a different, most trusting police officer.) So the image of Dr. Silberman running away from Arnold Schwarzenegger in a cemetery in 2003 remains the character’s final appearance.

I have no idea if Dr. Silberman shows up in this fall’s Terminator: Dark Fate — or if Earl Boen does, for that matter. (Given Boen’s retirement from screen acting shortly after Terminator 3, I highly doubt it.) Still, if I was trying to restart the Terminator franchise, Silberman is one of the first characters I would try to include — or, at the very least, one of the first I would try to emulate. Besides his efficacy from a storytelling standpoint, he provides a necessary counterpoint to the other main human characters onscreen, who are typically portrayed as heroic freedom fighters willing to lay down their lives in the name of preventing an apocalyptic future.

Dr. Silberman is the opposite. He doesn’t give a crap about the future — except maybe his own. He’s a career-minded cynic and a quintessential bureaucratic a-hole. He’s a reminder that there would be no threat to humanity from sentient computers without humans like Silberman, who are too oblivious and self-centered to stop their rise. And, if we’re being honest with ourselves, most of us are a lot closer to being a Dr. Silberman than a John Connor. It’s up to each of us to make sure we’re working to better ourselves, lest we wind up living out our own dark fate as the sniveling face of apathy and greed.
