Leonard Nimoy as the Voice of Sentinel Prime in Transformers: Dark of the Moon

Leonard Nemoy, the half-Vulcan, half-human Mr. Spock of the original Star Trek series, has joined the film as the voice of Sentinel Prime, the predecessor of Optimus Prime.

Director Michael Bay (not because his cousin, actress Susan Bay, was Nemoy's wife) could hardly make a better choice to give the voice for the aged Autobot seen at the end of the film's teaser trailer. Optimus Prime's wrecked body is the one who's seen found crash-landed on the moon by the Apollo 11 astronauts back in 1969. Soon, after being brought to earth, he takes the form of a fire engine in the movie's massive, climactic battle through Chicago.

Showbiz veteran who announced his retirement from acting last year after completing his turn as other worldly mad doctor William Bell on Fox's Fringe apparently backs at work. Nimoy recently talked about why he keeps doing public appearances when most actors would have retired:

I still feel an obligation to be out there for them, to tell them the ‘Star Trek' stories and to bring them up to date on what I'm doing. There's still a lot of interest.”

Mr.Spock also has a history with Hasbro's shape-shifting alien robots — he was the voice of Galvatron in 1986′s The Transformers: The Movie.

Obviously Bay has been open for course withdrawals with third Transformers movie and making a stronger story than the critically suppressed last one. Sense of that is giving the metallic features a bit more personality, even if they're villains. Nimoy's voice could be considered helpful.