There’s a dentist that goes to chicago to sell the head of his neighbor to the mafia. His neighbor is an hitman that the dentist’s wife hires to kill him. He screws with the hitman’s wife that everyone (including the hitman) wants to kill. The hitman gets friends with the dentist and the wife of the latter has to hire another assassin: the dentist assistance that is a fan of the hitman and is accepted as his apprentice. The wife then hires some random dude.
I could tell you who dies (or not), but I’m not the kind of guy that would spoil you the fun!