Quick: What does it take to craft a joke about a cat named Butthole farting out feathers? The answer is six writers, two actors, a cat, two directors and 20 years. Apparently.

Yes, there’s certainly a joke in there about half a dozen grown men (Sean Anders, John Morris, Mike Cerrone, Bennett Yellin and the Farrelly Brothers, Bobby and Peter) having to join forces like The Avengers of fart humor to bring a complicated film like "Dumb and Dumber To" to the big screen. But luckily, all that time and manpower went toward making a sporadically, if still sufficiently, funny movie.

In case there was a question about this matter, "Dumb and Dumber To" is – for lack of a better word – dumb. Very dumb. Dum dumb. There’s entertainment where you turn your brain off, and then there’s this, where maybe it’s best if you leave your brain out of the theater altogether just in case its rollicking, unrepentant stupidity is somehow contagious.

Reviewing movies is a subjective science, no more so than with comedy, so if you know this kind of so-lowbrow-it-can-barely-see humor isn’t your bag – which fair enough – I doubt "Dumb and Dumber To" will convince you otherwise. But when it comes to comedies, the most important critical box to check off is "Did I laugh?" And my answer to that question has to be yes. It’s certainly better than its bastardized prequel "Dumb and Dumberer: When Harry Met Lloyd" (a reference to a 1989 rom-com in 2003? Be careful out there on the cutting edge, "Dumb and Dumberer"), but that’s placing the bar much lower than need be.  

Two decades after the excitement of the first film, "Dumb and Dumber To" catches up with the misadventurous mouth-breathers Lloyd Christmas (Jim Carrey) and Harry Dunne (Jeff Daniels). They’re still living in the same beat-up apartment complex, still causing bird-related problems for the blind kid Billy in 4C and still very, very stupid.

What is new? Well, Harry now lives with a Bill Murray cameo. Oh, and Harry needs a new kidney. After visiting his few friends and adoptive parents (even though they’re Asian, this comes as news to Harry), options are looking slim. However, thanks to a former fling named Fraida Felcher (a tremendously game Kathleen Turner), Harry finds out he has a kid – and therefore a potential kidney-in-waiting.

Of course, they find out about this several decades after the fact, so Harry and Lloyd must set out across the country to find the now grown-up ditzy daughter Fanny (soap star Rachel Melvin) – the former looking for a kidney, and the latter secretly looking for love.

Like Lloyd and Harry’s odds of getting their Mensa membership, things weren’t looking good for "Dumb and Dumber To." Like anything coming out of hibernation after 20 years, the movie struggles to get its footing in the early going, with just a scattered amount of gags working, while many others come off surprisingly cruel.

The sequence involving Harry’s Asian parents is mighty uncomfortable, with the two leads behaving more racist than simply dumb. Many of their goofy antics seem to be trying to actively harm people, giving the proceedings an unpleasantly mean tint, and the script’s feelings toward women are awfully troubling, painting all the female roles as shrill wrinkly shrews, diabolical villains (Laurie Holden plays the main baddie, Fanny’s scheming, cheating, murder-minded adoptive mother) or, in the case of Fanny, sexual prizes to be fought over and won.

Turner gets it the worst with an extended gag based upon ridiculing her appearance. The punchlines sting and not in a good way. Like I said previously, she’s tremendously game.

These jokes feel like relics from a different era, and for that matter, so does the movie in its worst moments. Time and change have not been kind to the Farrelly Brothers’ comedic sensibilities – or their visual eye, which based on the flat, cheap and bightly lit sitcom-esque look of "Dumb and Dumber To," hasn’t budged an inch since "There’s Something About Mary."

The Farrellys and these braindead characters belong to an old-school style of humor, selling hard, going big and yanking out all the stops for every laugh. They sweat for every gag, something no longer in vogue with today’s audiences, currently hooked on the Apatow era’s vibe of everyday dudes chilling and quickly improvising on a couch. Carrey has suffered from the same problem, his wildly manic energy and larger-than-life hammy facial and vocal contortions no longer playing to today’s audiences. "Dumb and Dumber To" is a gathering of all-out entertainers, trying anything and going anywhere for even the cheapest laugh, and – fair or not – it often feels dated before they hit their punchlines.   

At the same time, the Farrelly’s untainted brand of humor gives "Dumb and Dumber To" an odd innocence – maybe not always with the characters or the content, but of intent. It’s a movie whose sole purpose is laughter, and even when the humor goes too far or dabbles in places it shouldn’t, there’s a sweetness and purity of purpose.

To balance out all that critical seriousness, here’s a reminder that a cat named Butthole eats meth and swings from a ceiling light.

Anyways, thanks to that sweetness, "Dumb and Dumber To" kept me on board during its early struggles. And as it staggered into a kind of comedic stride on the road as the boys try to beat Fanny to a Ted-esque science convention – alongside the villain’s devious exhausted henchman and foil (Rob Riggle, pulling double duty as two different heavies) – the movie and its sincere stupidity eventually won me over.

Carrey, Daniels and franchise newcomer Melvin’s deeply committed, delightfully eager performances deserve much of the credit as well. Carrey’s malleable face, expressions and reactions still make for an ideal comedic canvas, while Daniels shaggy, dumbfounded exuberance is a pleasure to see on screen again.

The movie packs in a ton of gags (as you would kind of hope from a movie with six writers). Several don’t work; just about equally as many do. It's a mixed bag, but it’s mostly worth it for some moments of inspired idiocy, like Lloyd and Harry first attempt at tracking Fanny from a letter sent to Fraida (pro tip: use the return address) or a nostalgia trip with the dog van that ends prematurely. There’s even some actual cleverness mixed in with all the farting and such, as with one gag involving birds, Pop Rocks and explosions that returns later on with a sneakily amusing twist.

Did "Dumb and Dumber To" have to really be made 20 years after the fact? No, probably not. The sequel certainly has its issues, and the story, involving a road trip to find a girl with killers in close pursuit, is nothing new for these doofuses. It’s one last dopey, bright eyed and bushy tailed guffaw. But it has enough laughs – even some big ones – and for fans and "Dumb and Dumber" agnostics alike, that will likely be enough merit its existence.

I fall toward the latter of those two options. I watched the original my freshman year of college, laughed a fair amount and then mentally tossed the movie away like a fast food burger wrapper. I’ve already started doing the same with "Dumb and Dumber To." But there’s nothing wrong with indulging in some junk food every now and then. Maybe just don’t make a habit of it.