As Psy did in his megahit Gangnam style and follow-up Gentleman, the direction of music video of Hangover is deliberately low-end style.
The music video is shot in Korea and it depicts how Koreans drink, get drunk, and get hangover hangover hangover hangover...
As the scenes are full of very Korean stuff, they may need some background knowledge to understand the hidden meaning.
I may be wrong, since I did not direct the music video. Yet as a Korean person, I can guide you what is so funny about it.
Here we go.
Scene 1. Psy is making a bomb shot domino.
Bomb shot is a mixture of glass of beer and a shot of Soju or whiskey, and Koreans love bomb shot as it expedite you get drunk.
Scene 2. Psy is drinking a hangover remedy. It's a kind of OTC medicine, and Korean people just love it. The scene is taken place in a convenient store, and Psy is eating a cup noodle and Snoop Dogg with a triangle shaped kimbap, a Korean style Onigiri. Unlike Americans eat pizza for hangover, Koreans gulp hot soup.
Scene 3. Koreans go to public sauna for hangover. They sweat and have a sound sleep to get sober.
Scene 4. Some Koreans drink more alcohol to get over hangover. The green bottle is called Soju, and it is one of the most loved liquor in Korea. It is very affordable and is higher than 18% alcohol, which means get drunk!
Scene 5. Koreans love to go to Singing Room, Korean style karaoke. They love to sing, and sometimes guys go there to get wasted with other ladies. These ladies are not the same as street girls, but definitely know how to rejuvenate the mood for guys.
Scene 6. It's taken place at the Wolmi Island nearby Seoul. This place famous for some of the joy rides. One is the rollercoaster viking, and the other is Disco Pang Pang.
Scene 7. This is the famous and notorious Disco Pang Pang. This wafer like coaster spins round and round with hip hop. The ride itself can be fun, but the real fun part is how DJ controls the ride with music with his dirty words. Think of a standing comedy show, and the comedian pick a table to amuse the rest.
Scene 8. At Korean billiards, you have to order Jajangmyun, which is a Korean style Chinese food. Why? You just have to.
Scene 9. Again Soju! This is like Vodka for Russian, and Beer for Badgers. Snoop Dogg and Psy does some fancy, handy work to open Soju. This series of ceremony takes place for nothing, just like a habit. But they had to do this when the brewery filter was imperfect in the past, and some unwanted debris were inside the liquor.
Scene 10. Psy and Snoopy Dogg is having a Love Shot. This is to demonstrate friendship and love between two persons. It doesn't matter if they are the same sex or opposite.
There are also some lyrics written in Korean, too.
Body shit miss
DAE CHE ODIL YES (대체 어딜 예쓰 / Where the hell, yes?)
QUIKORI MOCHA GETSU (꾀꼬리 못 찾겠어 / Can never find)
Eeny Meeny Miny Moe
Catch a lday by the toe
AN YEPUMYUN (안 예쁘면 / If she does not look pretty)
YEPU BOIL TEKAJI PARA PIRI PO
(예뻐 보일 때 까지, 빠라삐리뽀 / DRINK, until she looks pretty)
BADU SIYO (받으시오 / Let me pour you a drink.)
Hope this helps you understand the background of Hangover.