Friday casting news abounds: Shia LaBeouf has signed onto the cast of the upcoming "Indiana Jones" film, while Rachel Weisz has said no to a third undead romp with the "The Mummy" franchise, according to E! Online.

LaBeouf -- who can be seen in theatres right now in "Disturbia" and will appear in this summer's upcoming "Transformers" movie -- is not able to discuss what his role will be, although he has said, "I can tell you I'm sort of the sidekick character." While earlier rumors had pegged the character as Indy's son, this seems not to be the case, although since the film is still over a year away from opening, anything can change.

Director Steven Spielberg said, "We are excited about bringing Shia into our Indy family.

His talent has impressed not only his audiences throughout his young career but the directors, producers and fellow actors who have worked with him in his television career and now his film career."

Rachel Weisz's departure from the Mummy cast (due to scheduling conflicts) is much less heartening. While costar Brendan Fraser is still planning on returning, Weisz' absence may very well remove the heart of the series, as her character's on-screen chemistry with Fraser's character provided much of the fun for the series. Smallville creators Miles Millar and Al Gough are rewriting the script to account for the change in cast. Jet Li has signed for the flick, which will be set in China. The film is due out in theatres July 18, 2008.

In other casting news, Christine Ricci will be appearing in the upcoming "Speed Racer" flick, as can be found in the official press release.