Hangover 3 is predictable and not too funny except for scenes between Melissa McCarthy and Zach Galifianakis. McCarthy has a small but memorable part as Zack's love interest. The tag ending is a goof, too, as a sight gag so don't run out of the theatre even though credits begin.
All in all the writing by director Todd Phillips and Craig Mazin falls short of coming up for big laughs. Mild chuckle worthy, Hangover 3 is about the Wolfpack -- Bradley Cooper (Alan), Ed Helms (Stu), Zach Galifianakis (Alan), Justin Bartha (Doug) -- trying to create an intervention for Alan's mental issues. Alan's father (Jeffrey Tambor) dies and the Wolfpack agrees to drive Alan to the facility. This begins the trip that continues to the end of this wacky and weird road show. John Goodman (Marshall), who has been funnier, holds up the Wolfpack for money that Ken Jeong (Mr. Chow) allegedly has stolen from him.
While the audience was eager to laugh and laughing before punch lines in expectation of the humor of The Hangover, I sat through most of the film stone-faced. A joke would be set up, but the pay off wasn't there. The production values are top notch unlike the home movie look of that hit, Hangover. Goes to show you that a polished looking film does not relate to the laugh factor and level of humor. Oh, I wanted to laugh, but it just wasn't in my windpipe.
As to the acting, Bradley Cooper is smooth and his usual handsome self. Ed Helms is his deft, dry witted self, capable of a throw away delivery like no comedian I know. Zach Galifianakis is smooth and quirky and steals most of the scenes he is in -- except those with Melissa McCarthy who is triumphant as a horny store manager. Justin Bartha is played down and has little to do except be number four in the Wolfpack. Ken Jeong does not overact and director Phillips gets the maximum amount of laughs out of Jeong's frequently too broad performance.
Las Vegas becomes a character as much of this caper is filmed here. Hangover 3 is an infomercial for Caesar's Palace, Cooper, who lives with his mother, said on a talk show. He likes Vegas, but was leery of it as a steady diet or falling into "that Vegas thing." This franchise cannot endure a Hangover 4. Iron Man, it isn't. But it is fun, mild fare for a hot spring night. Give it a chance, but keep your expectations on the back burner.