2x13 - Maniac Mansion

A new neighbor moves in, and visits the Edisons. He's part of the witness relocation program because he ratted on a mob family. He thinks Fred is Tony, who was part of the gang. He also thinks that Fred is going to kill him. Fred sets him straight, and he's quite relieved. Later, two real men from the gang come looking for Hudgie, and get scared when they see Fred. They decide to meet at a local diner, and Hudgie has Fred pretend to be Tony. With the help of Harry, Fred and Hudgie fool the mobsters. He then moves to Calcutta to avoid being caught again by the gang.