'Transformers: Dark of the Moon': Leonard Nimoy joins voice cast | Inside Movies | EW.com Leonard Nimoy joins 'Transformers: Dark of the Moon' voice cast -- EXCLUSIVE Here is some news that should make Transformers: Dark of the Moon live long and prosper in the hearts of sci-fi fans. Mr. Spock himself, Leonard Nimoy, has joined the film as the voice of Sentinel Prime, the predecessor of Optimus Prime whose wrecked body is seen in the teaser trailer, found crash-landed on the moon by the Apollo 11 astronauts in 1969. Later, after being brought to earth, he takes the disguise form of a fire engine in the movie’s massive, climactic battle through Chicago. Apart from his obvious Star Trek cred, Nimoy also has a history with Hasbro’s shape-shifting alien robots: He was the voice of Galvatron in 1986′s The Transformers: The Movie. Transformers filmmaker Michael Bay had toyed with the idea of inviting him to play a voice in the second movie, Revenge of the Fallen, but wasn’t sure he could pay the veteran actor enough. “I was too scared to ask him,” the director says. “Plus, he’s married to Susan Bay, who’s a cousin of mine. So I had to be careful. I’ve met him at family functions. But he told me, ‘I would be honored. I’m glad to be back!’” Bay has been open about changing course with this third Transformers movie and making a stronger story than the critically pulverized last one. He says part of that is giving the metallic characters a bit more soul, even if they’re villains. “The robots have more character in this movie. Much more. You really understand their struggle, on both sides actually,” Bay says. The 3-D Transformers: Dark of the Moon opens July 1.