If, however, you have not seen The Hangover Part II, there's still no need to watch it - just go and see The Hangover.
There's nothing else for me to add here - except to retell the whole story of the first part and then just paste it here since........yeah, you get it......... IT IS THE SAME, for fuck's sake.
Monkey vs Mike Tyson - monkey wins.
p.s. Get lost, Zach Galifianakis.