The new "X-Files" movie will be packing more heat. Rapper Xzibit, Amanda Peet and Billy Connolly have signed on for director Chris Carter's next big-screen adaptation of the hit series for Fox. Sources said Xzibit and Peet will play fellow FBI agents to David Duchovny's Mulder and Gillian Anderson's Scully in the supernatural thriller with a stand-alone story, not a sequel or continuation of the hit 1998 feature adaptation. Citing a policy of secrecy surrounding the plot line, Fox would not confirm any details regarding the three actors' roles. Carter and Frank Spotnitz wrote the screenplay, and production is expected to begin this month in Vancouver. The film is set to hit theaters in July. Xzibit recently was cast opposite Bruce Willis and Woody Harrelson in Oliver Stone's "Pinkville," but his schedule was freed up when that film was put on hold because of the writers strike. The recording artist, who has finished shooting "American Inquisition," is known for his role in "8 Mile" and as host and producer of MTV's "Pimp My Ride." Peet also has signed to star opposite Mark Ruffalo and Ethan Hawke in Brian Goodman's drama "Real Men Cry" for Yari Film Group. The "Whole Nine Yards" star can now be seen in another alien-related film, the New Line drama "Martian Child." Scottish comedian Connolly, who received a SAG nomination for his role in 1997's "Mrs. Brown," has appeared in "Lemony Snicket's A Series of Unfortunate Events" and "The Last Samurai."