Specious Nephew — Fay Risner

A stranger shows up for Molly Moser's wedding. He claimes to be Melinda Applegate's nephew. An American version of Miss Marple, Gracie doesn't believe him. She's determined to prove he's up to no good. Gracie tries to warn the others, but they think she's jealous because Melinda's not having anything to do with her now. At the same time, all sorts of upheaval takes place at the mansion while Molly's gone on her month long honeymoon.