New 'Hangover Part III' Trailer: A Wild Intervention for Zach Galifianakis (Video)

The "epic finale" arrives in theaters May 24.
Warner Bros. Pictures

The hazy plot of Hangover Part III is becoming clearer.

In the second trailer for the sequel, the wolfpack gets back together to host an intervention for Alan (Zach Galifianakis) after the death of his father (Jeffrey Tambor).

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"Apparently he's been off his meds for almost six months," says Doug (Justin Bartha), in a foreshadowing of the mayhem to come. It doesn't look like the gang made it to New Horizons, a rehab facility. 

After a desert highway chase, John Goodman's villain makes an entrance, claiming that Mr. Chow (Ken Jeong) owes him $21 million. Errant gunfire, hotel hijinks and Chow commandeering a parachute over the Vegas skyline ensue. 

Watch below: