Shawn is forced to stay in Cory's room, in secrecy, because of a cherry bomb prank gone wrong in Alan's grocery store mailbox, which keeps him from going home. Cory keeps it a secret the best he can, but Amy and Alan know something is up because Mr. Feeny saw Shawn climb up to Cory's window. They play along until Shawn leaves and Cory comes clean with them. Shawn finally comes clean and goes back home. Shawn and Cory both learn valuable lessons. Shawn learns that he is not forced to be a bad kid and can be on Cory's "side of the line." (thetvdb.com)