Dirty Grandpa

Incompetence combined with the occasional burst of disreputable laughter makes Dirty Grandpa oddly lively for a movie that's largely terrible.

Equal parts bad and baffling, it seems to have been written and directed by alien life forms who read YouTube comment sections for a week and drew these conclusions about human behavior.

This is a movie that desperately wants to be a raunchy, politically incorrect, gross-out comedy. It gets as far as desperate.

Its horrible message: the old are only interesting when they're capable of aping the young.

Steer away from Dirty Grandpa, just as you would sidestep a dog turd on the pavement.

Plays like one of those dire mainstream films that - thanks to a few extreme moments - Quentin Tarantino periodically reclaims in his best-of-the-year list.

The premise has potential, but the execution is painfully unfunny.

The kind of film that, one day, De Niro's great-grandchildren will watch and wonder what all the fuss about him was.

Mazer can't decide what kind of film Dirty Grandpa is to be.

De Niro's legacy as an actor will be cemented with ground breaking films like Casino, Raging Bull, Taxi Driver, Goodfellas and Heat - just to name a few. Dirty Grandpa will not.