Lisa conducts a secret experiment for the Springfield Elementary School science fair to see who's smarter, Bart or a hamster. Meanwhile, Homer is forced to swear off beer after being arrested on a D.U.I.

After returning to Boston only to discover Frasier in bed with Rebecca, Lilith comes to Cheers to seek Sam's advice. Frasier comes after her, and Rebecca shows up as well to explain. Frasier says he can't take Lilith back after what she did - just as her lover, Dr Pascal, shows up and takes the gang as hostages unless Lilith returns to him. When Paul and John Allen Hill show up and also get taken as hostages, Lilith has to persuade Pascal to let them all go, and that she doesn't want to go back. Plus will she reconcille with Frasier?

George, Elaine, and Jerry volunteer at a retirement home. Elaine is grossed out by her resident; Jerry is assigned to a mean old man, who he loses when he takes him to get his dentures repaired. Meanwhile, Kramer and Newman try to make money by selling old records to a used record store.