If you like your humor broadside up, hold the subtlety, you'll want to nurse thisHangoverwith your best buds. The ensemble cast meshes perfectly--it's like a super-R-rated episode ofFriends: silly, slapstick, and completely in the viewer's face. When four pals go to Vegas to celebrate the imminent nuptials of one of them, they partake in a rooftop toast to "a night we'll never forget." But they're in for a big surprise: their celebration drinks were laced with date-rape drugs, so when they awake in their hotel room 12 hours later, not only are they hung over, but they can't remember what they did all night long. Oh, and they're missing the groom-to-be.The film is so cheerfully raunchy, so fiercely crude, that the humor becomes as intoxicating as the mind-altering substances. The standout in the ensemble is Zach Galifianakis, who is alternately creepy and hilarious. Ed Helm (The Office), in addition to his memory, loses a tooth in uncomfortably realistic fashion, and Bradley Cooper (He's Just Not That into You) has deadpan comic timing that whips along at the speed of light. "Ma'am, you have an incredible rack," he blares to a pedestrian from the squad car the guys have "borrowed." "I should have been a [bleeping] cop," he tells himself approvingly.Director Todd Phillips brings back his deft handling of the actors and the dude humor that worked so well inOld School, as well as the unctuous Dan Finnerty, memorable as a lounge/wedding singer in both films. But it's the nonstop volley of jokes--most cheerily politically incorrect--that grabs the audience and thrashes it around the hotel room. Just watch out for the tiger in the bathroom.--A.T. Hurley