Cam Gigandet and Nick Thune to Play Man and Member in Raunchy 'Johnson'

Johnson, a raunchy new comedy by screenwriter Jeff Tetreault, has signed Twilight and Easy A star Cam Gigandet and comedian Nick Thune to the lead roles of a bed-hopping womanizer and the penis that literally gets up and leaves him.

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Filming gets underway this week in Chicago, Il., for the independently-financed feature, with Huck Botko -- helmer of the Adam McKay- and Will Ferrell-produced The Virginity Hit -- set to direct.

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In the comedy, Gigandet plays Rich Johnson, a sexually prolific ladies' man whose overworked genitals literally abandon his body and take on human form, played by Thune.

Finding himself suddenly pitted against his favorite appendage, Rich must somehow convince his penis to return while "learning how to be a better man in the process," according to a synopsis.

“It’s semi-autobiographical," Tetreault tells The Hollywood Reporter. "Nick is only 6’4, though. Shaq would be more of an accurate physical representation.” 

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Johnson is a co-production of 2DS Productions & Roman's Empire, with Reid Brody, Danny Roman and Bill Ryan sharing producing duties.

“Jeff’s voice is a breath of fresh air in Hollywood and I am beyond excited to be making his first movie," Roman says.

Gigandet and Thune are both repped by WME.