Endora's latest spell transforms Darrin into a 73-year-old man. Thinking quickly when the Tates arrive, Samantha passes off Darrin as his own grandfather, Gordon. But there's even more trouble ahead when Larry Tate tries to match up "Gordon" with Louise's Aunt Millicent (Ruth McDevitt), a geriatric swinger. Sam solves matters in characteristic fashion by appealing to Endora's vanity. Written by Ed Jurist, "Samantha's Old Man" originally aired on December 3, 1970. ~ Hal Erickson, Rovi