“Dirty Grandpa”: 20 amazing facts about the movie! (List) February 25, 2016 By Rania Strataki Leave a Comment 1. Dirty Grandpa is a 2016 American comedy film directed by Dan Mazer and written by John Philips. The film stars Robert De Niro, Zac Efron, Zoey Deutch, and Aubrey Plaza. [Read more…] about “Dirty Grandpa”: 20 amazing facts about the movie! (List)