I'm not sure exactly when it happened, but at some point along the way the words “A Happy Madison Production” stopped meaning a silly, fun, dirty-at-times but altogether entertaining movie and started meaning avoid at all costs. I'd have to look at the facts and figures but by the time Adam Sandler was sitting in a kiddie pool full of blue pee, I gave up on him.

'That's My Boy' has more than enough pee jokes of its own (so much pee) but it's also got something else – Adam Sandler playing a character. It takes about sixty seconds with him as Bud-swilling, foul-mouthed, walking id Donnie Berger to - well, maybe admire is the wrong word, so let's say eagerly - sign on for a movie-length ride.

'That's My Boy' opens with a ridiculous, hilarious and slightly shocking pre-title sequence wherein a boastful 8th grade version of Donnie manages to live out every pre-teen's dream and shag the hot math teacher. The kid playing young Donnie is hardly a master thespian (and barely pubescent) which makes this sequence even more entertaining. To the tune of The Cult's “She Sells Sanctuary,” Donnie is discovered as a young Don Juan and begins life as “the 8th grader who got his teacher pregnant.”

Now it's twenty years later, the teacher's in jail, Donnie is broke and the kid (Andy Samberg) is a young neurotic about to get married. He's turned his back on his father, changed his name (from Han Solo to Todd) and is an upstanding hedge fund manager who, needless to say, needs a little Donnie Berger in his life. Donnie, barging in like Rodney Dangerfield crossbred with Jerry Lewis, is about to ruin, save, ruin again then (finally) save his son all in the course of one very hijinks (and fluids) heavy weekend.

You can see the ending coming a mile away (there are multiple ticking clocks to keep ya going) but all of that is secondary to the real point of the movie: get Sandler, the maniac, next to Samberg, the stick in the mud.

With the genie out of the bottle so quickly (I mean, there's a kid boning a Christina Hendricks-shaped teacher in the intro!) the script is game to go as blue as you can imagine and then push it even further. It's so extreme it isn't to be taken seriously – it's like the movie is set in an alternate universe where everyone is filthy all the time. The key thing is that, unlike, say, a piece of shameless, nihilistic garbage like 'The Hangover Part II,' there is a genuine warmth here. The movie wants you to have a good time, not to be extreme. It's disgusting, at times surprisingly so, but somehow still sweet. Sandler's Donnie Berger is a Candide of raunch comedy, and that generosity of spirit is something that's been missing.

'That's My Boy' is far from flawless. Some bits work better than others. Personally, I would've trimmed the “Grandma picks up semen-crusted kleenex” jokes by about half and, let's be very clear about this, no Nick Swardson is good Nick Swardson. But there are some wonderful flights into surreal territory. Donnie's super power is to make a can of beer appear from almost anywhere and pairing him with Vanilla Ice is quite inspired. There's a musical montage of drunken debauchery that may top the one from 'Wet Hot American Summer' in sheer WTFness. And the moment when Will Forte meets the stripper “Champale,” or the salute to Spencer's Gifts or, well...there are a lot of funny moments.

Whirling through all these gross-outs and dips from realism, 'That's My Boy' stays upbeat. The reconciliation between father and son (and a surprise cameo as grown-up Mom), as idiotic as it is, gave me genuine chills. Extra points, too, for rock and roll. The movie is wall to wall Van Halen, Rush, Argent, Ratt and Kiss and has some of the dopiest quotables since 'Step Brothers.' “Leap year, motherf---er” and “I'm gonna ride you like a Model T” being the two that, even out of context, probably sound funny.

Rating Meter 7

‘That's My Boy’ hits select theaters on June 15th

Jordan Hoffman was the movies editor at Hearst Digital’s UGO for four years and currently contributes to SlashFilm, MTV’s NextMovie and StarTrek.com. He’s made two marginally successful independent movies, is a member of the New York Film Critics Online and was named IFC’s Ultimate Film Fanatic of the NorthEast in 2004. Follow him on Twitter at @JHoffman6.