THE SAFEST PLACE to be in "Hangover 3" is the spot usually reserved for Justin Bartha - off camera.

Bradley Cooper and Ed Helms look like they're trying to sneak out a side door of this played-out franchise, happily ceding screen time to Zack Galifianakis and especially Ken Jeong. (Poor Helms doesn't quite make it - stay around for the end credits.)

An apt subtitle for the trilogy's finale would be "Chow Time" - Jeong's flamboyant mystery man is the driver of a gold-heist plot that has the wolfpack in Mexico trying to find Chow, key to locating missing bullion that belongs to a vengeful crook (John Goodman).

The guys end up for a time in Tijuana, the inevitable third corner in the series' triangle of debauchery (Vegas and Bangkok).

This time, though, no one involved - not even anything-goes director Todd Phillips - seems to have the appetite for the friends' brand of mass depravity.

No hermaphrodites, no Mike Tyson.

Zoo animals? Still part of the mix. In lieu of the tiger and the chain-smoking monkey, we get a brief cameo by a giraffe - the movie opens as a manic-phase Alan (Galifianakis) drives the animal down the expressway, heedless of an approaching overpass.

The giraffe stunt, we learn, is the latest in a series of outbursts by off-his-meds Alan, prompting an intervention and road trip that detours south of the border, and finally back to Vegas.

Along the way, we go through the motions of a heist/caper plot, the dull mechanics of which are a poor replacement for the lightning-in-a-bottle genius (and flashback execution) of the original, which so captured the imagination of the post-binge, hungover America in 2009, and still ranks as one of the top five time-capsule movies of the past decade - the one most likely to explain our Vegas-baby culture to mystified future generations.

It's in Vegas that the laugh-starved "H3" surrenders and follows the emergency procedure prescribed to every faltering comedy - hire Melissa McCarthy. She turns up as a pawn broker and looming soulmate for Alan who may do more for him than rehab.

If "H3" makes another bundle - and the prospects are not good - there may be some kind of spin-off built around the weirdo synergy of McCarthy and Galifianakis.

Otherwise, we can thank the movie for giving us a partial answer to a great trivia question: Name two movies in which a character smothers a bird. "Hangover 3," is one. The other, the Oscar-winning "Amour," only slightly less funny.

  There are too many funny scenes to count from the "Hangover" franchise. Come to PhillyDailyNews.com/TheConversation to vote on a few of our choices of the funniest, and share what we missed.

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