Samantha and the Loch Ness Monster

 is the third episode of the eighth season, and the 231st episode of the Bewitched series. The episode was completed by July 22, 1971.

Plot
Darrin and Samantha visit the town of Inverness, Scotland on Loch Ness, to see Darrin's cousin Robbie. At the lake, they see the Loch Ness Monster. Samantha reveals he is actually a warlock named Bruce, whom Serena had transformed into a monster forty years earlier. Samantha convinces Serena to change Bruce back, whereupon he takes legal revenge on Serena and turns her into a mermaid.

Trivia

 * Agnes Moorehead and David White did not appear and received credit only.
 * Greg Lawrence was uncredited for playing Adam Stephens.

Cast

 * Elizabeth Montgomery as Samantha Stephens
 * Dick Sargent as Darrin Stephens
 * Don Knight as Robbie
 * Bernie Kopell as Baron von Fuchs
 * Steve Franken as Bruce
 * Erin Murphy as Tabitha Stephens
 * David Lawrence as Adam Stephens
 * Pandora Spocks as Serena

Source
Bewitched, Season Eight episodes on Wikipedia. Retrieved on November 22, 2019.