Shia LaBeouf, the 20-year-old actor who stars in this summer's Transformers action thriller, has signed to co-star alongside Harrison Ford in the fourth Indiana Jones movie.

LaBeouf, whose Rear Window-style thriller Disturbia opens Friday is perhaps best known for his boyhood roles in Holes and the TV comedy Even Stevens. He has been the subject of speculation as an addition to the sequel's cast but was forbidden by director Steven Spielberg and producer George Lucas from revealing it until now.

""Up until about two weeks ago, it was little more than a rumor,"" he says. ""Literally, when I was saying, 'I don't know anything,' I didn't know anything. It was an act of faith. I have not read a script. I don't think anybody has.""

Online fans are guessing Indiana Jones will have a son for this go-round, but LaBeouf says he can't confirm such plot points. Even the time-setting for the movie is a secret. ""I can tell you I'm sort of the sidekick character, obviously,"" he says. ""I'm sure there are a lot of laughs at my expense, and some kind of creature crawling on me.""

/www.usatoday.com/life/movies/news/2007-04-12-shia-indiana-jones_N.htm?csp=34"">Read here for more."