To assist her daughter in a dress fitting, Endora transforms herself into a double of Samantha. While at the fitting, Robert Frazer, a young writer, becomes smitten with her. Endora decides to cavort with him as Samantha. Meanwhile, Gladys Kravitz thinks Samantha is having a secret affair. There are further complications when it turns out that Bob is an old friend of Darrin's. Endora shows up as Samantha at a dinner that Darrin, Sam and Bob are having. Bob now believes Endora is Sam's twin.

Endora hires Rollo to get Samantha away from Darrin, but her plan backfires when Rollo creates a love potion for Samantha but Endora drinks it instead. Endora is set to marry a client of Darrin's, but at the altar, the potion wears off.