This was one of those “comfort movie” days for me. I wasn’t in the mood for arthouse cinema or awards contenders, I just wanted to sit down and laugh. As much as I bemoan lowest-common-denominator dreck and thinly-plotted garbage, we all need something simple and easy once in a while. On occasion, it’s nice to pay for a ticket with complete and total certainty in what you’re buying.

For instance, when a film stars Johnny Knoxville and comes with the label of “Jackass Presents,” you know exactly what you’re getting.

The plot of Bad Grandpa (yes, believe it or not, there is a flimsy attempt at a plot here) concerns Irving Zisman, an 80-something man played by Johnny Knoxville in state-of-the-art age makeup. Irving just received word that his wife passed away, and the horny old drunkard is overjoyed to hear that he’s single again.

(Side note: The “corpse” of Irving’s wife was modeled after Catherine Keener, of all people. Keener herself was set to appear under heavy makeup in the film, but her scenes got cut for time. I imagine that her involvement came at the behest of her frequent collaborator, Jackass godfather Spike Jonze. The Oscar-nominated writer/director was also set to don age makeup and drag for the film, though his scenes were cut for time as well.)

Anyway, Irving’s new freedom turns out to be very poorly timed. See, his daughter (Kimmie, played by Georgina Cates) is being sent back to prison on drug charges — again — so she hands her son (Billy, played by Jackson Nicoll) over to his grandfather. But of course, Grandpa Irving doesn’t want a 10-year-old cockblocking him (those are more or less his words, by the way, not mine). So Irving arranges to hand Billy over to the boy’s scumbag father (Chuck, played by Greg Harris). Irving gets his freedom, Chuck gets a monthly check for child support, everyone wins.

The only problem is that Chuck lives over in Raleigh, North Carolina. Irving and Billy live in Lincoln, Nebraska. So the old man and his grandson go on a road trip, spreading mayhem and confusion through half the country as they go.

It would be a charity to call the story threadbare. If you don’t already know how the rest of the narrative plays out, you most certainly will by half an hour in. In fact, there came a time roughly ten or twenty minutes from the end when the film seemed to give up on the plot entirely. After Irving and Billy finally make it to Raleigh and their mission has been completed, the film keeps on throwing them into random shenanigans just because.

The only saving grace for this movie — indeed, the only reason why this movie could ever have gotten made — is that the production did not take place in a controlled environment. The stunts, the come-ons, the call-outs, and the illegal activities were all done in front of unsuspecting bystanders. Their reactions therefore become the basis of the film’s humor, and a few civilians even become unwitting participants in the plot.

Sure, it’s a gimmick, and it’s the only one that the film has. But sometimes, one solid gimmick is all you need. That’s especially true if the one gimmick is creatively used in different ways, to unique and increasingly potent results (see also: Tucker and Dale vs. Evil). And if you want a zillion different unspeakable methods of self-flagellation and public humiliation to a sinister degree, who better than the Jackass team to deliver?

Johnny Knoxville and friends are masters of what I like to call “brute force humor.” There is no level they won’t sink to. You think it’s bad enough that a boy and his grandpa start a farting contest in a crowded restaurant? Well, strap in and sit tight, because Knoxville will find a way to make it far worse. The filmmakers will be as shocking as it takes until everyone is either laughing their asses off or demanding a refund.

Yet some of the film’s humor is slightly more intelligent than that. A prime example is the climactic “beauty pageant” segment, in which Billy dresses in drag to enter a youth beauty pageant. Then, completely out of nowhere, Warrant’s “Cherry Pie” starts blaring while Billy starts pole dancing and Irving rains down dollar bills. Is it shocking and inappropriate? You bet your ass. But it’s really just a comedic exaggeration of the “Toddlers and Tiaras” crowd. A child is prancing around in a sexual manner onstage while a parental figure encourages the activity, just like any other beauty pageant. It’s a damning satirical portrayal of the darkness that’s already there, and of course everyone at the pageant is upset to see it.

And no, this segment has absolutely nothing to do with anything else in the movie, but I don’t care. The kindergarten-age beauty pageant circuit is such a sick and twisted show of perversion and corrupt ideas that I fully endorse any act of calling out their bullshit.

Attention must also be paid to the choice of our main characters. Remember, the crap in this movie is being pulled by an old man and his grandson. Old men and young boys tend to get away with much crazier shit, because the excuse could easily be made that they don’t know any better. This makes their actions shocking without making them entirely unbelievable, which helps sell the illusion to all the unaware bystanders.

Additionally, our protagonists’ disparate ages put them at an ideal position to comment on their surroundings in a humorous and incisive way. For instance, Irving gets to be the old white guy who stumbles onto an overwhelmingly black strip club while young male strippers abound for ladies’ night. Hilarity ensues. As for Billy, he acts all wide-eyed and innocent while asking the attendant of an adult store what her stage name is. So the poor woman has to try and explain the difference between an adult bookstore and a strip club to a kid who (she assumes) doesn’t know any better.

You might be wondering where the humor comes from, watching unsuspecting people look like total dolts. Well, it doesn’t. In truth, watching the innocent bystanders serves as a constant reminder that they could potentially be us. Whether it’s some kind of hidden camera stunt or someone who’s gone genuinely bonkers, we could easily meet someone this crass and outrageous. Hell, for those who ride public transit, it’s probably an everyday occurrence. As such, the movie allows us to watch these people from a safe volume while implicitly asking us to think about what we would do in that position.

This is the basis of the humor: We know everything that’s going on, even when the people onscreen don’t. It’s called “dramatic irony,” a classic device for comedy if ever there was one. The film also benefits from the “Wile E. Coyote Effect,” in which we get to watch an unlikeable character suffer physical abuse again and again with the absolute certainty that he’ll never be seriously hurt. Sure, there’s the possibility that Irving could get injured during a stunt, and there are a couple of times when it seems like someone is finally going to deck the guy. On the other hand, come on. This is Johnny Knoxville. The guy may be getting on in years, but he’s still pretty much indestructible at this point and everyone knows it.

Bad Grandpa is essentially critic-proof, since you already know what it’s about and whether you’re the type of person who should see it. Sure, there’s a half-hearted attempt at a story, a subtle satiric edge, and a huge portion of dramatic irony, but that’s not the focus of the movie. No, this movie is focused on outlandish stunts, crass jokes, and over-the-top shock comedy. That’s exactly the kind of stuff that Jackass is known for, and there’s still no one out there who does it better.

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