Characters:
Bradley Cooper - Phil Wenneck
Ed Helms - Stu Price
Zach Galifianakis - Alan Garner
Justin Bartha - Doug Billings
Heather Graham - Jade
Sasha Barrese - Tracy Garner
Jeffrey Tambor - Sid Garner
Ken Jeong - Mr. Chow
Rachael Harris - Melissa
Mike Tyson - Himself
Mike Epps - Black Doug
Jernard Burks - Leonard
Rob Riggle - Officer Franklin
Cleo King - Officer Garden
Bryan Callen - Eddie Palermo
I have fun watching the movie from top to bottom. It was so hilarious that have all this twist and twisted scenes. It is so not for the conservative types. Be sure to watch out for the ending credits. The pictures from their Vegas tour from the moment they started to get drunk. Hope you all enjoy the movie as I did. Sorry for the late edit.
This is the story of the whole movie. Warning: Spoilers.
Phil Wenneck was a grade school teacher, may be considered one of the bad ass in the movie. His character was like a man that is so bored with his life. Stu Price is a dentist always claiming to be a doctor with a fiancee that is so tight and had sex with a bartender on a cruise (or was it in a plane?). His character was such a goody-two-shoes that Phil always badmouthed about his girlfriend.
Allan Garner is Tracy's very weird brother. He always has his own world but there was a scene in the movie that he said "he was a lone wolf, but after he met Doug he felt that he wasn't alone anymore. That his pack went up by 1."

When they arrived in Las Vegas they immediately checked-in in Caesar's Palace. Phil insisted that they should get a villa rather than Stu's already reserved room. At first, he was hesitant because his girlfriend constantly checks his credit statements. But eventually they take the villa. After settling in, Phil make the three change so they can get started with the party. While Stu is changing and talking with his fiancee, the others came in and making hurrying him up so they can party. After talking with his girlfriend, Stu takes out a small box that holds a beautiful ring. It was Stu's grandmother's ring. He revealed that he was going to propose to his girlfriend after the wedding ceremony. Phil was against it but they were shut off when Allan came in.
The four waits up in the elevator when Phil noticed Allan's bag and gave insults. The four continuing their trip to Vegas continue to the elevator and go up instead of going down. The three really did planned to go unto the rooftop. Allan revealed what's really in the bag. It's a booze for the toast they're going to make for the official bachelors party. Each shared their own message for the soon-to-be-groom and toast for the celebration.
The next day, nobody knows what happened last night along with the strange things surrounding them. Their hotel room wrecked, Doug's missing mattress, a chicken in the living room, a tiger in the bathroom and a baby in the closet. Things get worse when they found out that Doug was missing, his phone was left in the room. So they try to retraced what happened last night. While trying to remember what happen, Stu saw the hospital bracelet on Phil's so they rushed out to their first stop... The Hospital.
Before they even got to the hospital another weird events happened. The mattress was in one of the statues and the car isn't Sid's beloved car... it was a police car. No time to waste and be picky they rushed to the hospital. After talking to the obviously annoyed doctor, they were given a hint where they might have another clue. A small church, the kind of church which accepts on-the-spot wedding (It's really Vegas baby!).
Every clue and hint they find, they found theirselves in a loop hole. It just goes round and round. With every answer they found themselves in yet another problem or puzzle. But 5 hours before the actual wedding, Black Doug (not their bestfriend and soon-to-be-groom) gave Stu a hint that could lead them to where Doug is. And luckily, they found Doug sitting on the rooftop unconscious. After a very long day, they rushed to the wedding. After a lot of bad lucks they finally they received good luck. They came exactly on time.