If the sudden appearance of a surprisingly stretchy prosthetic penis trapped inside a soda machine at the hands of a horny old widower in Jeff Tremaine’s ‘Bad Grandpa’ doesn’t drive you out of the theater, you’ll likely do just fine with the latest entry from the ‘Jackass’ crew and their ever-shrinking bag of gross-out gags.

After all, Johnny Knoxville’s eponymous “bad grandpa” Irving Zisman starts humping the vending machine within the film’s first five minutes, making it crystal clear what sort of production we’re in for. 'Bad Grandpa' is the latest from the creative team behind ‘Jackass,’ taking one of their favorite character creations on the road for one of the most ill-fated and weirdly amusing road trips in recent cinematic memory.

The plot of ‘Bad Grandpa’ (and yes, there is one) centers on the recently widowed Irving, a first class horndog who is pleased as punch to be finally free after the death of his wife. Irving may be ready to live life on his own terms for the first time in decades, but we already know that his drug addict daughter is about to foist his oversharing grandson Billy (Jackson Nicoll) on to him. Because this is a ‘Jackass’ film, that hand-off happens during one of the most uncomfortable and wickedly hilarious scenes the group has ever put together, a funeral scene for the ages. Saddled with young Billy, Irving sets off to deliver him to his dirtbag dad in North Carolina. What’s that sound? Oh, right – road trip!

To say that hijinks ensue is an understatement, as the film is entirely built on the outlandish, inappropriate, and frequently classless gags the pair pull while on the road, and “hijinks” is woefully inadequate at explaining some of the jawdropping stuff that Tremaine and his team turn out. Much of the humor of ‘Bad Grandpa’ is placed in the hands of total strangers – or, better yet, on the faces of total strangers, as the film delivers in spades when it comes to innocent citizens reacting in appropriately mortified ways. Oddly enough, the very human reactions of non-actors consistently highlight just how deeply weird both this film and Knoxville’s character actually are.

For at least the first half of the film, Knoxville and company adeptly moves back and forth across the line between “horrifying” and “humorous,” and ‘Bad Grandpa’ is able to stir equal parts laughter and mortification in its audience. Tremaine and his scribes have built a seemingly never-ending stream of gags inside the narrative, even if they’re quite loosely assembled together. The best gags are the ones rooted in reality (albeit, a very skewed one) – Irving trying to mail Billy in a giant box, the pair of them raiding a grocery store, Billy asking strangers to be his new dad – and when Knoxville goes at it alone, from a stint at a bingo parlor to a trip to an all-male dance revue, the film suffers. It’s just going for shock value at that point, and while it may amuse at the time, the returns are diminishing.

The true joke of the entire film, however, is that it is a joke, and we all know it, even if most of Knoxville and Nicoll’s co-stars are unwilling and unaware participants (kid actor Nicoll even seems questionably complicit from time to time). Most of the victims of the numerous pranks are apparently accepting enough, though there are only a few instances of blurred out faces, so who knows how many takes the production had to go through with certain bits if too many participants objected to being shown in the final product.

‘Bad Grandpa’ could not exist as an actual feature or a real documentary – it can only exist in its strange, fake middle ground, the only safe place for such senseless and often offensive gags, material that would be pummeled in any other narrative set-up. “It’s just a joke!” a sign should flash during every scene of ‘Bad Grandpa.’ “Don’t be insulted by the silly, goofy jokes! Jokes!”

Knoxville is admirably adherent to his shtick, which may just be the biggest problem with the production. He never once breaks character, even in scenes that see him driving alone with young Billy, a feat that would be more effective if Irving ever felt consistent as a character. He’s in on the joke, we’re in on the joke, but that doesn’t make it funny. In fact, knowing that the entire film is a goof frequently makes it feel woefully uneven and unsatisfying, especially because Tremaine consistently cuts off gags just as they’re getting to the good stuff, presumably because the real life people involved are reaching tipping points that must be diffused by someone finally stepping in to say, “it’s okay! We’re making a movie!” (And we know they do this, because such scenes pepper the film’s end credits.)

Despite its aims to stand as a more traditional narrative outing than the ‘Jackass’ boys are used to, the film retains the surveillance and hidden camera style of filming they've used for previous productions, lending it a nice little bit of consistency to the rest of the ostensible franchise, no matter how different the film tries to be. But as ‘Bad Grandpa’ begins to wind down the clock, it becomes an unexpected mish-mash of new ideas, both narratively and technically. Suddenly, the film aims for some emotional weight (sure, it’s light, but it’s definitely there), with Billy begging his grandfather to keep him instead of delivering him to his deadbeat dad, a plot point that fuels the film’s disappointing finale. Tremaine and Knoxville also lean on a strangely placed flashback scene to tell a nonessential story, along with a surprisingly long sequence set at a kiddie pageant that doesn’t make a lick of sense, even if it’s very funny.

In fact, that’s the real problem with ‘Bad Grandpa’ – for all its outlandish gags and big time laughs - is that the production doesn’t make much sense, and for a film aiming to feel narratively complete, that’s a massive misstep. There’s no question the ‘Jackass’ crew is still funny and irreverent enough to make a film, but a fictionalized feature is something they should stay far away from the next time they hit the road.


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