At this point, it’s like being reunited with old friends.

Old friends around whom you should never, under any circumstances, consume Jagermeister. Or marshmallows. Or pretty much any substance that could mask a powerful sedative.

"The Hangover Part III" rarely hits the delirious highs of the original installment. On the other hand, it never falls into the been-there, seen-that repetition of the second.

This time, there’s no wedding, no bachelor party, no blackout, no dalliances between Stu and a prostitute, no goofily improvised song from Stu, no Mike Tyson … man, "The Hangover Part II" really was just an Asian spin on the first movie.

Two years after they returned from Thailand, Stu (Ed Helms) — still sporting the faintest hint of his lasered-off face tattoo — is happily married, as are Phil (Bradley Cooper) and poor, neglected Doug (Justin Bartha).

Alan (Zach Galifianakis), though, may be the happiest of them all.

He’s first seen, Hanson’s "MMMBop" blasting from his stereo, howling his Wolf Pack howl, blissfully towing his newly acquired giraffe down the freeway. (Spoiler alert: It doesn’t end well.)

The 42-year-old manchild, who considers 45 minutes of skee-ball a workout, soon falls into a downward spiral that pulls back the curtain on what made him such a freewheeling, lovable character: severe mental illness.

Yeah, that kinda puts a damper on the hijinks for a while, even though viewers must have known all along that, as Hank Hill would say, that boy ain’t right.

After a painfully awkward intervention, Phil, Stu and Doug agree to hit the road again, taking Alan to a treatment facility in Arizona, and things fall into a more familiar rhythm. Phil acts coolly indifferent, Alan displays new depths of his man crush on Phil, Stu shrieks hysterically and Doug goes missing for large chunks of the proceedings.

This time, his disappearance is at the hands of Marshall (John Goodman), a violent criminal from whom Chow (Ken Jeong) stole $21 million in gold. After roughing up the boys, Marshall cuts the trio loose with an ultimatum: Deliver Chow within 72 hours or he’ll kill Doug.

Yeah, it’s still a comedy.

Their pursuit of the diminutive, clothing-challenged gangster, earlier seen Shawshank-ing his way out of a Thai prison behind a "Hang in There" kitty poster, leads them through Tijuana and, ultimately, back to Las Vegas.

Instead of merely aping its predecessors, this final chapter of the "Hangover" saga — once again from director and co-writer Todd Phillips — really feels like the end.

Their current predicament can be traced back to their original drug deal and their original drug dealer, Black Doug (Mike Epps). That’s one of several callbacks to "The Hangover," including checking in on Jade (Heather Graham) and Baby Carlos — err, Tyler (Grant Holmquist, one of several infants who played the role in the original).

But "Part III" also is an opportunity for new beginnings. Especially for Alan and Cassie (Melissa McCarthy), who bond in her downtown Las Vegas pawnshop over their shared love of Billy Joel in a mating ritual that’s nearly as sweet as it is disturbing.

The Wolf Pack is back, and although each of "the three best friends that anyone could have" gets his turn to shine, this is primarily Alan’s journey.

You don’t expect character growth in raunchy, R-rated comedies, but it should warm your heart to see him evolve from the weird loner who plays Words With Friends even though his father (Jeffrey Tambor) reminds him he doesn’t have any friends. (Alan: "You can set it on random!")

There are some stumbles along the way. Most notably, much like the Wolf Pack, the rest of the movie struggles to get a handle on Chow.

Although "Part III" is the darkest installment yet, there are still more than enough laughs to go around.

Even if the most uproarious ones are saved for the closing credits.

With those final, fleeting moments, though, Phillips and his particular brand of merry mayhem accomplish the oldest of showbiz maxims: Always leave them wanting more.

Christopher Lawrence is the film critic for the Las Vegas (NV) Review-Journal. Contact him at clawrence@