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.
Nimoy was previously the voice of Galvatron in 1986′s The Transformers: The Movie.
Michael Bay had wanted to ask him to provide a voice for the second film, "Revenge of the Fallen." "I was too scared to ask him," the director told the magazine. "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 added "The robots have more character in this movie. Much more. You really understand their struggle, on both sides actually."
Starring Shia LaBeouf, Rosie Huntington-Whiteley, Josh Duhamel, Tyrese Gibson, Kevin Dunn, Julie White, Frances McDormand, John Malkovich, Ken Jeong, Patrick Dempsey, Alan Tudyk and John Turturro, Transformers: Dark of the Moon hits 3D, 2D and IMAX theaters on July 1.