It starts out with this guy planning a bank robbery... he seems to have it all together, but we soon find out that he's a screw up and a wimp. His planning goes very well indeed, but the next day when he starts his plan in motion - he hits a huge snag at his first stop and never even makes it to the bank. He tries to find a mask to hide his identity at a convenience store and all they have is a child's size. He decides to just swipe it, but the clerk discovers his attempt and tries to stop him. He ends up shooting the clerk in the arm and the clerk chases him down the street - we learn through a series of flashbacks where he got the gun and that the clerk is high on heroine... During their foot chase, they bump into a member of the mafia or a gang or something and the clerk (who has the gun now) accidently shoots a woman. The gangster sets chase after the clerk with a knife. The three of them run throughout the day and into the night having multiple flashbacks that reveal how they are all connected. The also pass by a woman and all have similar fantasies about her (a somewhat misplaced and raunchy part of the film, but it does serve as a bit of comic relief). They end up running together and crashing into another mafia's hideout or whatever you want to call it which is about to be busted in on by a rival mafia/gang (triad?) as well as a group of cops. It all comes down to a standoff with guns and knives and stuff... I'd tell you how it ends, but I don't want to give it all away.