Tony's parents are going out of town so he decides to have a big party at his house. His little sister, Tess, threatens to tell on him if he doesn't let her and her friends come, too. Meanwhile, the three friends and Jerry are desperately trying to think up a way they can get into the party, which is sure to be the bash of the year. They finally succeed by getting on each other's shoulders and disguising themselves as two big guys from the city and putting on a hat and a coat and using baseball bats as arms. A couple of nasty biker youths get wind of the party and decide to crash it. They bust in, and start threatening everyone. At that moment, the three friends and Jerry who have been dancing start to lose their balance on the dance floor. Flailing with their baseball bat arms in an attempt to keep their balance, they hit the biker youths who flee in terror. Impressed by this show of heroism, the girls' interest in them becomes so intrusive that they unmask the three friends and Jerry
Tess und ihre Freundinnen gehen zu einer Party ihres Bruders Toni. Auch die drei Freunde versuchen alles, um mit dabei zu sein. Jeder auf der Party glaubt, Frank und Eric seien die Freunde von Monika. Als diese jedoch mit ihren echten Kumpels auftaucht, gibt es Ärger.