The first official trailer for The Hangover Part III has hit the Internet and it claims that this is the last go-round for Phil, Stu and Alan. Too bad, because we really like seeing Bradley Cooper, Ed Helms, and Zach Galifianakis party it up. In this new trailer the boys are back in Vegas, despite Stu saying that he swore he would never return there. Melissa McCarthy makes an appearance as what would appear to possibly be Alan’s new love. Also of note: Heather Graham is back! The Hangover Part III is scheduled for release on May 24, 2013.