‘Bad Grandpa,’ Worse Grandkid: Meet the 9-Year-Old Who Outfunnies Johnny Knoxville

Forget about his age, nine-year-old Jackson Nicoll delivers the comedy performance of the year in "Bad Grandpa," the next big shocking comedy from Johnny Knoxville and his band of merry Jackass pranksters.

Nicoll hadn't even been born with the first "Jackass" movie hit theaters in 2002, but the budding star got Knoxville to double over in laughter (and in pain) when the pair sat down with Yahoo Movies in Las Vegas. Watch the hilarious duo in action:

"Bad Grandpa" returns Knoxville to some familiarly funny territory; he's been dressing up like 86-year-old Irving Zisman and messing with unsuspecting real people for several years now. But in this new movie, Irving's got his little grandson Billy (Nicoll) to add a whole new, dastardly chunk of hilarious bait to the hook. The two of them set off across America, ostensibly to reunite Billy with his long-lost dirtbag father, but actually it's just a good reason to go mess with innocent people.

The fact that poor, unsuspecting folks get so royally worked over might be acerbic, were it not for the kid. Nicoll is just raw, pure, good comedy. You can see how much fun he's having; whether or not the humor comes at the expense of unwitting bystanders is for the adults to surmise.

[Related: Johnny Knoxville Up to His Old Tricks in 'Bad Grandpa']

There's obviously something inherently wrong with allowing a nine-year-old to perform such inappropriateness – like impersonating a little girl while totally rocking a striptease at a child's beauty pageant – but then, there's also something so inherently right. Laughter don't lie.

Originally from New Hampshire, Jackson Nicoll was just five-and-a-half when his mother brought him along when his older sister Jayden went to an audition. The casting director noticed Jackson's irrepressible personality and recommended him for a role in David O. Russell's "The Fighter." He won the part of Christian Bale's son in the Oscar-winning drama, which lead to bigger roles in the comedies "Arthur" and "Fun Size" (where he first met Knoxville).

Nicoll and Knoxville make a formidable comedy team, especially considering how their scenes were largely improvised around real people who had no idea they were being filmed. Knoxville did tell The A.V. Club that, since Jackson was so young, the filmmakers did invent new nonsensical phrases to substitute for real dirty language. Knoxville said, "We came up with terms like, 'Oh, I'd like to knuckle up on her pilaf' or, 'I'd like to hog race that 'spitooli,' just gibberish stuff."

"Jackass Presents: Bad Grandpa" is now playing.