It has been reported that Star Trek`s Leonard Nimoy will provide the voice for Sentinel Prime. This won`t be the first time Nimoy works in a Transformers project, because he did the voice of Galvatron in the 1986 animated film The Transformers: The Movie.
There is also more information in regards of the character on the film SPOILER ALERT:
According to EW, Sentinel Prime is brought to Earth, and he takes the disguise form of a fire engine in the movie’s massive, climactic battle through Chicago. I hope that instead of actually fighting in the final battle, Sentinel Prime just goes around trying to put out all of the fires caused by the fighting between the other transformers.
The movie stars Shia LaBeouf, Rosie Huntington-Whiteley, Josh Duhamel, John Malkovich, Tyrese Gibson, Frances McDormand, and Ken Jeong.
The official synopsis of the film:
The Autobots, led by Optimus Prime, are back in action, taking on the evil Decepticons, who are determined to avenge their defeat in 2009’s Transformers Revenge of the Fallen. In this new movie, the Autobots and Decepticons become involved in a perilous space race between the U.S. and Russia, and once again human Sam Witwicky has to come to the aid of his robot friends. There’s new characters too, including a new villain in the form of Shockwave, a longtime “Transformers” character who rules Cybertron while the Autobots and Decepticons battle it out on Earth.
Transformers: Dark of the Moon is set to open in 3D on July 1, 2011.