Justin Timberlake continues to add film projects to his expanding résumé. The pop star has signed on to join longtime girlfriend Cameron Diaz in the cast of the forthcoming animated feature "Shrek 3," according to a USA Today report. The film will also see stars Eddie Murphy and Mike Myers reprising their roles in the franchise's third installment.

But "Shrek 3" producer Aron Warner wants to make one thing clear about Timberlake's casting: Diaz had nothing to do with Justin landing the part. Timberlake earned it, Warner told the national daily newspaper.

"Our desire was to get somebody who is visible and had their own persona to bring to the table," Warner explained. "Justin fit the bill perfectly."

Timberlake will voice Artie, a teenage King Arthur who has no interest in his claim to the throne. Shrek, the affable green ogre played by Myers, is enlisted to help teach Timberlake's character how to act like royalty.

Diaz voices Shrek's wife, Fiona. Coincidentally, in "Shrek 2," a poster of "Sir Justin" hangs in young Fiona's girlhood bedroom. Warner said that in "Shrek 3," Fiona becomes pregnant, and that much of the film's plot revolves around Shrek coming to terms with his impending fatherhood.

Though audiences have yet to see him in a featured role on the big screen, Timberlake is no stranger to acting. He stars alongside Kevin Spacey, Morgan Freeman and musician/thespian LL Cool J in the upcoming film "Edison" (see [article id="1485506"]"Justin Timberlake Goes To Court To Prep For Film Role"[/article]). Timberlake plays Joshua Pollack, a young journalist who teams up with a grizzled, jaded reporter and an investigator for the district attorney's office to uncover an elite unit of corrupt cops.

The singer/actor will also be seen in Nick Cassavetes' "Alpha Dog," playing a fictional member of a drug gang led by Jesse James Hollywood, who orchestrated the kidnapping and brutal murder of a 15-year-old in August 2000 (see [article id="1492828"]"Justin Timberlake To Begin His Life Of Crime Next Week"[/article]). The film also stars Sharon Stone, Dominique Swain and Bruce Willis.

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