'Dirty Grandpa' trivia and fun facts
The screenplay for this film was featured in the 2011 Blacklist, a list of the "most liked" unmade scripts of the year.
The first poster art for the movie references the famous film poster used for 'The Graduate' (1967).
Zac Efron in 'Neighbors' (2014) dressed up as Robert De Niro's "Travis Bickle" character in Taxi Driver (1976).
Jeff Bridges and Michael Douglas were considered for the role of Dick Kelly before Robert De Niro was cast.