'The Hangover, Part 3' has returned to its old stomping grounds in Las Vegas where it was filming this past weekend and we see goofy Alan (Zach Galifianakis) wearing a very familiar outfit. So what does this tell us about the secretive plot of the third 'Hangover' movie?

In the scene being filming below, Galifianakis is wearing the exact same outfit he wore in the first film, complete with leather satchel. Filming was taking place outside a liquor store with Mike Epps as "Black Doug" returning. So what brings these two characters back together?

As it turns out, they might not be back together as much as we're getting a look at them meeting for the first time. If you remember back to the first 'Hangover' film, Alan admits he bought ecstasy from a drug dealer (later revealed to be Black Doug) at the liquor store (the ecstasy would later be revealed to be roofies). So it looks as if 'The Hangover, Part 3' is some parts a prequel that highlights some scenes we didn't get to see in the first movie.

Early reports stated that 'The Hangover 3' would follow the attempts to break Alan out of a mental hospital but it also follows antics in Tijuana (a small town in Arizona recently doubled for the Mexican city during production), so it's unclear how this all fits together.

'The Hangover, Part 3' hits theaters on May 24, 2013.