Sam falls off the wagon and Diane has a nervous breakdown after the breakup. But after she's cured, Diane returns to Cheers to recommend her psychiatrist--Dr. Frasier Crane--to help Sam. But she doesn't say that she's involved with him.
Diane tells Sam that she's seeing Frasier. Then, they both confess that they no longer have feelings for each other, even though both suspect the other is lying. And since the feelings are supposedly gone, Diane takes her job back.
Frasier tells Sam that the girlfriend of one his "clients" called out another man's name in bed, but Sam knows he's talking about Diane. Meanwhile, Cliff is afraid to tell a burly colleague that he's the fellow mailman who got him fired.
Cliff meets the woman of his dreams at the bar on Halloween night but is afraid of meeting her when he's not in costume, and Sam and Diane have their first non-romantic outing together after the breakup.
Sam accidentally shoots himself in the rear end after a confrontation with a jealous husband, but he changes the story when he tells it to the bar to make himself look like a hero.
Diane tries to make a good impression on Frasier's mother. But after their first meeting, Frasier's mother warns Diane that if she continues to see Frasier, that she will kill her.
Diane develops an allergy believing it's Frasier's dog after they move in together, but Sam and Frasier know her allergies are psychosomatic. Meanwhile, the guys at the bar shower Carla with a series of gag birthday gifts.
After a health scare, Norm gives up his old life and says he's moving to Bora Bora. However, he chickens out at the last minute and hides out in Sam's office. Meanwhile, Carla becomes depressed after losing a tip wager with Diane.
Diane warns Sam not to go out with a friend she met at the mental hospital because she has obsessive issues with men. But Sam doesn't heed the warning, and puts himself in a situation that he's afraid to get out of.
Much to Frasier's horror, his psychiatry mentor becomes involved with Carla and asks her to marry him. But she doesn't want to, even though she has just found out that she is pregnant with his baby.
Diane gets mad at the guys when she finds out that they took Frasier on a "snipe hunt." But she also doesn't want them to tell Frasier that they played a trick on him.
Norm gets in trouble with the law after he helps Cliff out by finishing his mail route, and Cliff hangs him out to dry. Meanwhile, Diane gets stuck underneath the bar while trying to check the heating system.
Sam makes plans for a romantic getaway with a local journalist. But Diane overhears parts of his conversations and jumps to the incorrect conclusion that he is making plans to spend the weekend with her.
Sam hires a waitress that Carla considers to be a perfect replacement for Diane: she's smart, talented and charming, and Sam doesn't want to sleep with her. But then her sexy daughter shows up at the bar and potentially ruins everything.
Carla believes that one of her customers is her old evil Catholic school principal, and she wants to get revenge on her. Meanwhile, Cliff claims to be receiving love letters from a woman he met on his Florida vacation.