Peter Cullen's Final Role Was On A Current Hit Superhero Series

Peter Cullen, the legendary voice actor, passed away on August 26, 2026, after a long career bringing countless characters to life. He is most renowned for his portrayal of Optimus Prime in the Transformers franchise, spanning animated series, live-action movies, and video games. However, his final role was on the critically acclaimed superhero TV show, Invincible.

Invincible, an animated series available on Prime Video, centers around Mark Grayson, a teenage boy who gains superhuman abilities following the arrival of his alien father, Omni-Man, portrayed by J.K. Simmons. The narrative takes a dramatic turn when Omni-Man is revealed as a villain, sent by the Viltrum Empire to conquer Earth. Mark subsequently joins the Coalition of Planets, a galactic alliance led by a character voiced by Cullen, Thaedus.

Cullen, known for his deep and commanding voice, brought Thaedus to life, a pivotal figure in the fight against the Viltrum Empire during the second season of Invincible. The character's introduction during Season 2 demonstrated the significance of Cullen's voice in shaping the show's narrative.

Robert Kirkman, the creator of Invincible, expressed his appreciation for collaborating with Cullen, describing it as a test of his professionalism. He stated, "Just flat-out, every fiber of my being was screaming, 'Don't ask him about Optimus Prime... Just be a professional, come on.'" Nonetheless, Kirkman found immense gratitude in Cullen's contribution to the series, stating that hearing his voice throughout the recording sessions brought him to tears.

Kirkman fondly recalled that he had been hearing Cullen's voice since his childhood, making it particularly poignant when his own dialogue was brought to life by the same voice actor. Cullen reprised his role as Thaedus in Invincible Season 4, released in 2026, making it his final credited project before his untimely death on August 26, 2026.