Dirty Grandpa

At least the title is accurate in Dirty Grandpa, an aggressively crude and low-brow comedy that finds its stars laughing all the way to the bank while leaving moviegoers with nary a chuckle.

This misguided monstrosity strains to be edgy and outrageous, completely oblivious to the fact that there’s hardly an original idea therein. The film is vulgar and obnoxious instead of being funny, and not smart enough to know the difference.

Dick (Robert De Niro) is mourning the death of his wife. Or is he? Right after the funeral, he ropes his lawyer grandson, Jason (Zac Efron), into driving him from Atlanta to southern Florida for a road trip and some male bonding.

But Dick soon reveals his true intentions during a detour to Daytona Beach for some spring-break debauchery. The old man is a pervert whose primary goals are getting laid by an amorous college coed (Aubrey Plaza) and screwing up Jason’s life as he prepares to marry an uptight Jewish girl (Julianne Hough). Hijinks ensue involving a drug dealer and a pair of buffed-up lacrosse players. Yet as Dick behaves like someone a third of his age, there’s some bitterness beneath the horny exterior.

De Niro obviously has fun with his freewheeling role, in which an early scene he refers to masturbating as “taking a number three.” And that’s one of the better jokes. Efron fulfills the straight-man role with his shirt (and pants) off much of the time, which seems appropriate under the circumstances.

The blame lies mostly with British director Dan Mazer (I Give It a Year) and rookie screenwriter John Phillips, whose script doesn’t really tell a story as much as it just strings together a random series of raunchy and sophomoric gags – very few of which hit the mark – without regard to taste or coherence.

What’s worse is the film shoots its comic wad within about the first 20 minutes, making the remainder practically intolerable. Most appalling is how the film, despite being totally detached from reality, brazenly expects the audience to care about the redemption of its protagonists.

The screenplay might have been scribbled on a bathroom wall before being put to paper. It’s targeted at frat boys who are either wasted or dared, while everyone else should try to avoid being trampled during a stampede for the exit.

Rated R, 102 minutes.