Watch The Hangover for Free: How to Stream the Movie Online at 123Movies. . When three friends finally come to after a raucous night of bachelor-party revelry, they find a baby in the closet and a tiger in the bathroom. But they can't seem to locate their best friend, Doug – who's supposed to be tying the knot. Launching a frantic search for Doug, the trio perseveres through a nasty hangover to try to make it to the church on time.