Sheriff Tupper's sister Winnie comes to Cabot Cove to escape her husband, Elmo. Despite their busy schedules, Amos and Jessica do their best to make her feel welcome, and Dr. Hazlitt also steps in to help. However, Winnie's husband and in-laws quickly show up in town as well, and Jessica's effort to show hospitality goes horribly wrong when Elmo dies from a dose of barbitals in her clam chowder after a fight with his wife. Can Jessica exonerate Winnie?
This episode includes examples of the following tropes:
- Big Damn Heroes: Deputy Marigold bursts into Jessica's house demanding to know about an illegally parked car, but once she sees Kenny is threatening Jessica and Harold, she pulls out her gun and makes him surrender.
- Continuity Nod: When a lady calls asking for someone to help get her cat out of a tree, Sheriff Tupper tells her that his deputy who used to handle matters of that sort resigned from the force.
- Crazy Jealous Guy: Elmo's jealousy stood among the characteristics that drove Winnie's endurance to the breaking point. He went so far as to hire private investigator Ed Bellamy to spy on her, and Bellamy tells Jessica that he stuck to his belief she had cheated on him even when Bellamy reported she had done things like see a movie alone.
- Everyone Has Standards: Harold explains to Jessica that everyone in the family (except Winnie) knew about Elmo's addiction problems but didn't really do anything to help him, but he's quietly horrified when Jessica makes Kenny reveal that he's Elmo's killer.
- Innocent Cohabitation: After her in-laws and husband descend on her brother's house, Winnie runs to Seth's in the middle of the night. Saying she didn't know the way to Jessica's or the hotel, she asks him to let her spend the night. She tells Jessica the next morning that she locked her door and closed her blinds, but Seth still calls Jessica in a panic when she asks him, knowing how much small towns gossip about this sort of thing.
- Just in Time: The new deputy walks in to talk to the owner of an illegally parked car and aims a gun at Kenny, keeping him from knifing Jessica or Harold to keep them from revealing he killed Elmo.
- Never the Obvious Suspect: Repeated twice.
- Winnie takes ulcer medicine that contains barbitals. She hid from Elmo in a town where her brother leads the law enforcement and the two had a nasty fight shortly before he died. However, she's innocent.
- Ed Bellamy, the private eye Elmo hired to keep tabs on his wife, fought Elmo on Jessica's lawn the night Elmo died and had outstanding expenses Elmo had refused to cover. Much to Amos' dismay (as his sister is the other primary suspect) his account checks out as accurate. He didn't kill Elmo either.
- Obnoxious In-Laws: The unpleasant behavior of Winnie's in-laws fits right in with her husband's abusiveness. Flo shoots barbs at everyone and sneers at Jessica's hospitality. However, the worst is Kenny, who killed Elmo and had no qualms about letting Winnie take the blame, or about killing others to keep the secret.
- Profane Last Words: According to Dr. Hazlitt, the last thing Elmo said was an obscenity.
- Shout-Out: The title refers to the song "Who Threw the Overalls in Mrs. Murphy's Chowder?"
- Tampering with Food and Drink: Kenny gave Elmo a bourbon laced with phenobarbital and put more in the chowder, both to finish the job and to make everyone think Elmo had only gone to sleep like the others until it was too late.
- Turn in Your Badge: Amos declares he knows his sister couldn't have murdered Elmo, and says, regardless of how suspicious the circumstances look, he would sooner resign as sheriff than turn her in.
- Would Rather Suffer: When a midnight caller (the private investigator Elmo hired) asks him to wake up Elmo, Amos refuses, saying that he would sooner throw a burning match in gasoline.