Peter Cullen's 5 Best Sci-Fi Movies And TV Shows That Aren't Transformers

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The prolific voice actor Peter Cullen died at the age of 85 on August 26, 2026, "surrounded by his loving family" in his LA home, per Variety. Cullen was best known for voicing Optimus Prime in the "Transformers" animated series from 1984. While he wasn't the only actor to play the character, he was by far the most prolific. Cullen gave Optimus his iconic stoic bass and was so synonymous with the character that he was the only G1 alum to voice characters in the poorly received-yet-popular live-action "Transformers" movies.

He emulated his brother, a Marine Corps captain, to create the Optimus Prime voice and demeanor, saying that his brother told him to "be strong enough to be gentle," which left a lasting impression on the young actor at the time and led him to landing the iconic role (via TFCon on YouTube). Yet a voice actor cannot live on one gig alone.

Cullen gravitated toward many sci-fi projects, but he also found himself playing the memorable Eeyore in "Winnie the Pooh" from 1988 onwards, Monterey Jack in "Chip 'n Dale: Rescue Rangers," and many more. When it comes to science fiction projects, though, Cullen stood out, and his passing will be felt, leaving many fans to say, "You know who would have been great in that role?"

The creative soul of Disney is in dire straits, with the company thinking the best way forward is to prioritize soulless live-action remakes of beloved classics, despite being proven time and time again that they just don't work. That said, the live-action strategy can succeed, just with a few tweaks. It could give underappreciated gems like "Treasure Planet" new life, a science fiction reimagining of the classic tale "Treasure Island."

The movie inserts many sci-fi staples into the mix, including aliens, laser pistols, and advanced robotics, but keeps 18th-century stylings, from clothing to ship riggings. It's a novel concept that would be unique if Level-5 hadn't used the same design principles for the game "Rogue Galaxy," but that game doesn't have the vocal talents of Peter Cullen. Sort of.

If you watched the entirety of "Treasure Planet" and wondered who Peter Cullen voiced, we don't blame you. He played Captain Nathaniel Flint, whose only "spoken" lines are the word "Fire!" and some laughs. It's a blink-and-you'll-miss-it moment that is quite frankly overshadowed by the narrator, the late great Tony Jay, but it's still one voiced by Peter Cullen.

Self-driving car technology has been advancing so fast you'd think it's trying to win a drag race. However, there's still a long way to go, as reliable self-driving cars are so few and far between. Regardless, many engineers are continuing to research and improve the technology to make life easier. That, and because they were inspired by science fiction projects like "Knight Rider," a classic 1980s crime drama with a unique premise.

The main star, Michael Knight (David Hasselhoff), partners with a self-driving, weaponized, and artificially intelligent car, KITT (voiced by William Daniels). This buddy cop pairing goes on episodic adventures fighting all sorts of crime. While KITT is unique among fictional AIs in that it never goes rogue, the show did dive into that trope with the help of Peter Cullen. Everyone likes a good, evil doppelganger, and for KITT, that was KARR.

KARR was the prototype model for KITT, and it wants revenge for being replaced. The character only appeared in two episodes. In the first, "Trust Doesn't Rust," KARR is voiced by Peter Cullen, but in the other episode, "KITT vs. KARR," Paul Frees stepped in for the role. KARR also returned in the "Knight Rider" reboot/sequel that ran from 2008 to 2009, with Peter Cullen behind the vocal wheel, albeit with a more Optimus Prime-y voice and the ability to transform, just to solidify the reference.

After Peter Cullen demonstrated his voice acting chops with the likes of Optimus Prime and Eeyore (and Venger in the "Dungeons & Dragons" cartoon), he became a bit of a hot commodity. You need someone with a deep, bassy voice that commands respect and attention? Hire Cullen. And that's exactly what many showrunners did. If you have an Amazon Prime Membership, your subscription comes with multiple perks, such as access to Prime Video, and "Invincible" is currently one of the top shows on the platform.

This R-rated superhero series is an adaptation of the graphic novel of the same name and mostly follows the original story. "Invincible" has a star-studded cast of actors, including Steven Yeun, J.K. Simmons, Seth Rogen, and, as of season 2, Peter Cullen. He plays Thaedus, a Viltrumite (the premier aliens of the canon) who, while not the main character, is pivotal to the story due to his actions in the past. Without going into details for the sake of spoilers, but if you know, you know. Cullen joining the cast was a huge win for the show. Tragically, "Invincible" is Cullen's last credited project.

So far, all of the movies and shows mentioned are available on one streaming platform or another. However, a good number of series and films are considered lost media, and while some are better left forgotten, "Megas XLR" is not one of them. "Megas XLR" was a Cartoon Network show that embodied the rebellious spirit of the aughts. It revolved around Coop, a slacker mechanic who somehow found a way to pilot a giant mech from the future by attaching a Plymouth muscle car where the head should be and cramming in more weapons than should be possible.

Each episode parodied popular culture genres, usually anime, and one-off characters were often voiced by actors associated with this culture. Peter Cullen was asked to voice two unrelated characters in two different episodes. The first, "Coop D'etat," was a double reference, as Cullen was joined by Frank Welker (Megatron from "The Transformers"), and they played giant robots that heavily resembled the Japanese mecha Mazinger Z and Raideen, respectively.

In the second episode, "A Clockwork Megas," Cullen voiced an evil warden who rules a planet filled with robots with an iron fist. Although, in true "Megas XLR" fashion, there is more to this character than meets the eye. Unfortunately, since Cartoon Network's executives classified "Megas XLR" as a tax write-off, you can't find the show on any streaming platform.

What's the difference between a good voice actor and a great voice actor? A good voice actor delivers a solid performance, but a great one can mask their voice so well that you don't know they're behind the microphone. Those chirping monkeys and braying oxen you hear in a film might be live animal recordings, or they might be the product of actors like Frank Welker and Peter Cullen. The movie "Predator" needs no introduction. This 1987 classic stars Arnold Schwarzenegger as he leads a team of soldiers against one of the most iconic aliens in cinema: the titular Predator — Yautja if you want to get technical.

Keven Peter Hall brought the creature to life as the suit actor (Jean-Claude Van Damme originally played the Predator back when it looked like a bug out of "Power Rangers"), but Peter Cullen provided the pipes. Cullen based his performance on an encounter he once had with a dying horseshoe crab. The Predator's iconic clicking and guttural noises were based on the crab's final crackling sounds. This wasn't the only time Peter Cullen was asked to provide noises for an iconic creature, either, as he also voiced some of the mogwai in the original "Gremlins" movie.