As filmmakers, Peter and Bobby Farrelly are outrageous, bodaciously socially incorrect and sometimes crude as hell. But there's also something supremely generous-spirited about them. That may be exactly the thing that derails "Me, Myself & Irene" as a comedy: The picture never builds the same ramshackle momentum that "Dumb & Dumber" and "There's Something About Mary" do, and for the first time the Farrellys don't seem as sure-footed about the tone they want to strike. It's not that they grab for laughs -- it's more that they let them slip by. "Me, Myself & Irene" feels so relaxed that it ends up seeming vague and indistinct. Leaving the theater, I couldn't quell those waves of disappointment: It just should have been funnier.

And yet I'm not sure it could be more likable, in its own gangly, off-kilter way. Jim Carrey, as Charlie Baileygates, a sweet-tempered, generous Rhode Island state trooper with a split personality -- his obnoxious, aggressive alter ego goes by the name of Hank -- could carry the movie admirably with his physical comedy alone. But as he's developed the character, and as the Farrellys, along with co-writer Mike Cerrone, have written it, you end up feeling a degree of sympathy for Hank even as you're forced to face up to his more unsavory qualities -- his fondness for footlong dildos, for instance.

That's partly a measure of Carrey's skill as an actor, but it probably has just as much to do with the Farrellys' pervading sensibility. As outlandish as they are, there's a definite skillfulness to their touch -- it was apparent even in their first feature, "Dumb & Dumber," a work of über-booger genius.

But there's also a kind of delicacy at work in the Farrellys' movies; the secret is that they have a way of being compassionate that never gets uncomfortably squishy. For one thing, any human being with an infirmity, a deficiency or even just a skin color (any skin color) is fair game for their jokes: They're equal-opportunity pranksters. I'd take that even further and say that what has made the Farrelly brothers' movies so beloved -- as opposed to just successful -- is the fact that people who are "different" don't make them nervous. Most of us grew up with at least one kid who was, as we used to say before we were made to feel anxious about it, retarded, and we can all recall the various ways in which those kids were treated. In my own recollections, everyone would try to be nice to those kids, but no one except the smallest handful really felt relaxed around them. The Farrelly brothers may not always be particularly nice, but the great playground of their work comprises all the cruel tricks that life can spring on us, and they want everyone to feel welcome to laugh and play without any self-pity or awkwardness.

The Farrellys' barbed compassion is evident in "Me, Myself & Irene"; too bad the gags aren't as memorable. Charlie Baileygates is the kind of guy who takes his lumps and doesn't seem to mind them. He looks the other way when his wife takes up with a vertically challenged African-American chauffeur who's also, as she is, a Mensa member. He looks the other way when she gives birth to black triplets (explaining away their dark skin with devil-may-care denials like "My great grandmother was half-Italian"), although he makes no secret of the fact that he adores them. And he looks the other way when his wife leaves him, which is when his troubles begin.

Charlie can't deal with his painful feelings, and so he shoves them into some dark, hidden corner of his psyche, where they fester and eventually reveal themselves in the guise of hotheaded Hank. Hank and Charlie both have the same Marine-style crewcut, but the similarity pretty much stops there. When Charlie snaps, every muscle in his face seems to stretch taut, and the faintly loopy gleam we've seen in Charlie's eyes hardens into a cartoonishly funny, menacing glare. (He looks like something that might have sprung from the pen of Chuck Jones, which gives us a suggestion of how wonderful he might be in his next project, a remake of "How the Grinch Stole Christmas.") Charlie was a patsy, the guy who just wanted everyone to like him; Hank is the id unleashed, the one who barks orders instead of taking them and who throws punches like a demented prizefighter. In short, he's not gonna take it anymore.

Now playing: Read all the recent movie reviews by Salon's critics