Jackass Presents: Bad Grandpa

The wrongs pile up, and there's a clear object of satire. That feels new for the Jackass experience: a target that isn't a crotch. I'd like to see Irv try to strike again with braver gags.

Onlookers occasionally glance into the camera, a pretty good sign that people are hip to these prankster movies now and just play along.

Secondhand gags, third-rate execution, fourth-rate results.

Some of the jokes are flat-out hilarious, but most are overworked or tepid.

The trick to such humour involves persuading the audience to squirm and laugh at the same time. Grandpa triggers merely the squirming, and you can get that from a mild case of haemorrhoids.

Bad Grandpa has no goals whatsoever beyond making you snort with base, moronic glee, but when it scores, it scores.

Plenty of things want to be funny, but Bad Grandpa bites off more than its dentures can chew this time around.

Amidst all the chaos and naughtiness, there's an unabashed celebration of the human spirit here that left me simultaneously laughing and crying.

You can laugh at poop and fart jokes for only so long; sooner or later all the pooping and farting will start to stink.

With his 8-year-old grandson riding shotgun, Knoxville just keeps on punking the real world with carefully constructed shonky shenanigans. Do not try this at home. Do feel free to laugh.