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, Rovi