Having robbed and thoroughly destroyed a gas station, a group of street thugs with their own gripes against society sit in a convenience store and out of sheer boredom, decide to rob the same gas station (as the title card reads, "Why do they attack the gas station? Just because!"). But, since the manager had the foresight and sense to stash the money away, the four gang members take the manager and the employees hostage and stick around, dispensing gas to all the customers and keeping the money.
A range of characters stop for gas throughout the film, not all with good intentions, but with ludicrous results. A gang of school bullies come by the gas station to harass one of the employees for money (they end up being taken hostages, while the bullied employee ends up being forced into a fist fight with one of the bullies... and wins) The police come by demanding free gasoline (the four thugs refuse, as the police clearly aren't doing their job). A customer refuses to pay for a full tank of gas, only asking for half a tank, and is taken hostage. More school bullies come by the gas station, seeking revenge for the first fight, but then they too are taken hostage. The four titular thugs also order unusually large amounts of food from a Chinese restaurant, and the deliveryman becomes suspicious.
It's not long until they start attracting the wrong kind of attention, which leads to a violent confrontation with the police and further gang members. The fight ends when No Mark sprays everyone in the chaos with gasoline and threatens to throw a lighter at them. The four thugs escape while everyone else remains panicked at the gas station.
During the credits, four scenes show what the characters do after the events in the film: Paint appears to be a successful painter, but he angers a customer when he celebrates by spilling red paint all over one of the paintings. Rockstar restarts his career as a lead singer, and he bosses his members as they prepare for their next performance. Bulldozer becomes a policeman, and he scolds teenagers for smoking. He punishes the kids the same way he dealt with the hostages, and warns them about their futures by alluding to his own past. No Mark joins a baseball team, but accidentally hits the catcher while pitching.
