Two mischievous schoolboys, Penrod and Sam, are constantly in trouble at school. They start their own club, the In-Or-In club, of which they are the only members. Two of their schoolmates, Georgie and Rodney, want to get into the club but are not allowed because they`re always ratting out Penrod and Sam to the adults, and getting them in trouble. However, George`s father complains to Penrod`s father about it, who tells Penrod that they must admit the two boys. Penrod and Sam decide that if they`re being forced to accept the two stool pigeons, they`ll make them pay for it.