Dermot Mulroney Joining Zac Efron, Robert De Niro in 'Dirty Grandpa' (Exclusive)

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Dermott Mulroney

Dan Mazer is directing the comedy from QED and Lionsgate

Dermot Mulroney is in negotiations to join Zac Efron and Robert De Niro in Dirty Grandpa, the comedy from QED and Lionsgate penned by John Phillips.

Dan Mazer, who's worked with Sacha Baron Cohen on Borat, Bruno and The Dictator as a writer, is directing. Barry Josephson is producing.

Efron will play a young man who is tricked into driving his grandfather (De Niro), a perverted former Army general who thinks his grandson is about to marry the wrong woman, to Florida for spring break.

Mulroney will play Efron’s father and De Niro's son.

Shooting is due to begin later this month.

Mulroney recently wrapped a starring turn in horror project Insidious: Chapter 3. He is repped by WME and Jackoway Tyerman.

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