Miffed that Darrin refuses to allow Samantha to use witchcraft, Endora dispatches Sam's lookalike cousin, Serena, to the 14th century, there to cast a spell on one of Darrin's ancestors. As a result, the modern-day Mr. Stephens is transformed into a warlock for a 24-hour period, and the havoc wreaked during those 24 hours obliges Sam to take a little visit to the past as well. Though
Elizabeth Montgomery plays both Samantha and Serena, the latter role is credited to one "
Pandora Spocks," as it would be in virtually all future episodes featuring Serena. Written by Ed Jurist, "The Return of Darrin the Bold" originally aired on February 4, 1971. ~ Hal Erickson, All Movie Guide