The Hangover

Doug's bachelor party brings together four very different men.

Phil is the confident schoolteacher desperate for a break from ordinary life. Stu is a dentist trapped in a controlling relationship. Doug is the relatively sensible groom.

And then there's Alan.

Socially awkward, unpredictable and newly determined that his future brother-in-law's friends are now his friends too, Alan immediately changes the chemistry of the group.

They climb into Doug's father-in-law's prized Mercedes and head across the desert towards Las Vegas.

At this point, the plan still seems perfectly reasonable.

That doesn't last long.

The four men toast Doug on the roof of Caesars Palace.

Then the film jumps forward.

Phil wakes on the floor.

Stu is missing a tooth.

Alan discovers a baby.

The suite looks as though somebody detonated a bomb inside it.

And Doug has vanished.

The decision not to show the previous night's events gives The Hangover its brilliant central structure.

The audience knows exactly as much as Phil, Stu and Alan do.

Nothing.

Every new discovery becomes another piece of a completely insane puzzle.

The trashed suite contains plenty of mysteries.

None are quite as difficult to explain as the fully grown tiger in the bathroom.

The discovery captures the movie's basic joke: every answer raises an even bigger question.

Where did the tiger come from?

Why is there a baby in the room?

What happened to Stu's tooth?

Where is Doug?

And why does nobody remember any of it?

The only way forward is to retrace their movements through Las Vegas and hope somebody else remembers what they did.

Unfortunately, plenty of people do.

A hospital wristband provides one of the first useful clues.

From there, the Wolfpack begins following the trail backwards.

They discover they visited a hospital after Stu somehow lost his tooth. They learn that the police encountered them during the night. They uncover a stolen police car.

And eventually they discover something even Stu wasn't expecting.

He got married.

The bride is Jade, a Las Vegas escort and the mother of the baby currently travelling around with them.

Stu's supposedly respectable life is beginning to look very different from the one he remembers.

Just when finding Doug seems difficult enough, another figure enters the mystery.

Leslie Chow.

Ken Jeong's explosive appearance immediately changes the film's energy. Chow believes the group has something belonging to him and isn't particularly interested in their claims of amnesia.

A misunderstanding involving another Doug makes matters even worse.

The Wolfpack suddenly finds itself trying to recover money while also trying to locate the right missing man before his wedding.

Vegas has stopped being a party destination.

It's become a crime scene they created themselves.

Eventually, the bathroom tiger's origin becomes clear.

It belongs to Mike Tyson.

During their forgotten night, the group somehow stole it from his property.

That creates a fairly obvious problem.

They need to give it back.

Getting an enormous tiger into the back of a Mercedes is difficult enough. Keeping it there proves considerably harder.

What follows is another reminder that the missing night wasn't merely wild.

It was apparently completely unhinged.

And the people responsible are now cleaning up after versions of themselves they don't remember being.

Underneath all the madness sits an increasingly urgent deadline.

Doug is supposed to be getting married.

His bride believes everything is under control.

Phil is desperately trying to maintain that illusion while the group searches Las Vegas for any trace of the groom.

As hours disappear, the possibility that they won't find him becomes increasingly real.

Then Stu finally notices something.

The mattress from their hotel suite isn't in the room.

It's outside.

And suddenly Alan's earlier behaviour on the hotel roof makes sense.

Doug never left Caesars Palace.

After the group drugged themselves during their rooftop toast, they eventually returned to the same location and left Doug stranded there.

He's been on the roof ever since.

Sunburned, furious and very much alive.

The discovery is beautifully simple because the solution sat above the characters for almost the entire movie.

Now they have another problem.

They need to get from Las Vegas back to Los Angeles before the wedding.

Fast.

The journey back becomes a race against time.

Doug has spent his bachelor party trapped on a roof.

Stu has lost a tooth and ended up with a Vegas marriage.

Phil has spent hours lying to Doug's bride.

Alan has somehow turned a group of reluctant acquaintances into something resembling actual friends.

But they make it.

Doug reaches his wedding.

And despite everything that happened, the bachelor party appears destined to remain something the four men can only partially reconstruct.

Until Alan remembers one final detail.

Alan discovers a camera.

And unlike the men who attended the bachelor party, the camera remembers everything.

The photographs contain the night's missing pieces.

The group agrees on a deal.

They'll look at them once.

Then delete them.

The closing credits finally reveal glimpses of the chaos the film has spent its entire running time reconstructing.

It's the perfect punchline.

We've spent the movie imagining what happened.

Now we finally get to see just how bad it really was.

The film's success depends heavily on the chemistry between its central trio.

Bradley Cooper's Phil provides swagger and confidence. Ed Helms turns Stu's increasing panic into some of the movie's funniest moments.

And Zach Galifianakis' Alan became the breakout character.

Rather than three interchangeable comedy leads, each member of the group reacts to the disaster differently.

That chemistry became the foundation for the sequels that followed and turned the group into one of the most recognisable comedy ensembles of the period.

The Hangover arrived with a wonderfully simple idea.

Don't show the wild bachelor party.

Show the consequences.

That decision turned a familiar premise into a mystery in which every clue makes the previous night more absurd.

The film became a huge commercial success and transformed its central cast into major comedy stars, while lines, images and situations from the movie quickly entered pop culture.

It also created something nobody involved in Doug's bachelor party would have wanted the following morning:

A franchise.

The Wolfpack would return.

And somehow their next trip would go even worse.