One practical joke after another created by witchcraft is the first introduction Darrin has to Samantha's favorite uncle and the black sheep of her family, Uncle Arthur. Seeing Darrin's antagonistic relationship with Endora, Arthur offers to help him by giving him one spell to get back at Endora whenever she needles him, that spell which will make her disappear. Darrin refuses Arthur's help until Darrin faces one antagonistic encounter too many with Endora, at which time he relents to Arthur's request. What Darrin is unaware of is that Arthur has been the cause of much of his latest grief which he attributed to Endora, and that the outrageous spell is another of Arthur's practical jokes as it has no effect beyond the amusement factor of Darrin saying the nonsense words, ringing a cowbell and blowing on a duck whistle with much fervor. Once they find all this out, Samantha, Endora and Darrin believe Uncle Arthur is the one who needs to be taught a lesson.
—Huggo