Orson Welles recorded his final film performance on October 5, 1985. Five days later, the man who had reinvented American cinema with Citizen Kane was dead of a heart attack, at 70. But the last character he ever gave voice to wasn’t a person, a detective, or a wizard. It was a planet — a sentient, world-devouring robot named Unicron, built for a Saturday-morning cartoon spinoff that nobody expected to become one of the strangest footnotes in Hollywood history.

A Planet With an Ego to Match

By 1985, Welles was a legend running on fumes — brilliant, broke, and mostly reduced to voiceover work and wine commercials to bankroll film projects he could no longer get financed. So when an animation studio approached him about voicing a villain in The Transformers: The Movie, nobody guessed it would matter much. Story consultant Flint Dille recalled that Welles, ever the showman, was delighted once he understood the scale of the part: “I’m playing an entire planet!” he reportedly told the production team, savoring the sheer absurdity of it.

Unicron wasn’t a robot in a planet costume. He was the planet — a moon-sized, world-consuming entity that transforms into a towering mechanical god and swallows entire worlds for fuel. It’s the kind of galaxy-scaled menace that usually gets a career voice actor with decades of monster-movie credits. Instead, the filmmakers landed the man who directed Citizen Kane — and his own feelings about the part were, fittingly, contradictory. He reportedly told biographer Barbara Leaming shortly before he died, “You know what I did this morning? I played the voice of a toy. I play a planet,” while separately grumbling to colleagues that the script amounted to “all bad outer-space stuff.” Critics who’ve revisited the recording since say his talent shows through anyway — his Unicron reads less like a cartoon villain and more, as one retrospective put it, like “a bored god.”

A Voice Too Weak for the Job — Salvaged by a Synthesizer

The recording session itself tells you how far Welles’s health had declined. According to voice director Wally Burr, Welles could not pick up the pace of his line readings no matter how many takes they ran — and rather than argue with a Hollywood titan mid-session, the crew let him read at his own tempo and fixed it in post. Engineers sped his dialogue up by roughly eight to ten percent, then pitched the audio back down electronically to restore his signature bass rumble. His actual voice, by that point, had grown so thin that technicians had to run it through a synthesizer just to salvage a usable take — meaning the Unicron audiences heard in theaters is, technically, a processed hybrid: Welles’s real performance, digitally reconstructed into something closer to his younger, thunderous baritone.

Despite the technical scramble, Welles finished the job. A persistent urban legend claims he died mid-recording and never completed his lines — but voice actress Susan Blu and director Nelson Shin have both confirmed he recorded all of his dialogue before his death, and no lines were re-recorded or replaced by another actor. In one more grim coincidence, Unicron’s monstrous roars were repurposed from a 1982 Incredible Hulk recording by actor Bob Holt — who had also died before the film reached theaters.

The Death That Traumatized a Generation

Welles’s casting wasn’t even the movie’s biggest shock. The Transformers: The Movie also killed off Optimus Prime, the noble leader millions of kids had grown up trusting as an indestructible father figure — a decision driven largely by Hasbro’s desire to retire old toy molds and sell new ones. The studio badly underestimated the emotional fallout. Story consultant Flint Dille later described the theatrical reaction bluntly: “Kids were crying in the theaters. We heard about people leaving the movie. We were getting a lot of nasty notes about it.” One child, Dille said in the same interview, “locked himself in his bedroom for two weeks” after watching his hero die on screen.

It became one of animation’s first mass lessons in generational trauma marketing — a toy commercial that accidentally taught an entire cohort of eight-year-olds what grief felt like, delivered in the same 90 minutes that gave a dying cinematic giant his last words on film.

Two Endings, One Strange Legacy

Nearly four decades later, The Transformers: The Movie occupies a bizarre dual place in pop culture: it’s remembered as the animated feature that scarred a generation of children, and separately, as trivia-night gold for film buffs who can’t quite believe Orson Welles’s last credited role was a planet that eats other planets. Both things are true, and neither cancels the other out — which might be the most fitting tribute to a filmmaker who spent his whole career blurring the line between prestige and spectacle, right up to his very last take.