Endora pops into Samantha and Darrin's room while they are still sleeping. She awakens Samantha and asks her to go to the Sacred Volcano. Samantha declines. Endora insists, but Samantha refuses. Before she leaves, Endora says, "This is the black day for us. This is Halloween." Darrin wakes up, and seeing Samantha sitting up, asks her if she had a bad dream. "No. I'm just starting one."
The next morning Samantha receives a package from Darrin. Inside it are pictures of stereotypical witches. Endora thinks he's another bigoted mortal. "Darrin wouldn't do a thing like this," Samantha defends. She calls him up at the office, unhappy. Darrin says he knows nothing about the witches' hats. Larry Tate is there, and says he sent them. Darrin gets angry, saying witches' hats are obscene. Larry says he sent them because they were made by the company of their client, whom they would be entertaining that evening. Endora later pops into Darrin's office asking him to let Samantha go to the Sacred Volcano. Darrin refuses.
That night, before everyone arrives, Darrin has a tray of small bags for trick-or-treaters. Three arrive, and Darrin gives each a bag. "Thank you very much," the biggest one says. Endora is out on the lawn, and they ask her for some candy. "Don't push me," she says. The boy says he has to trick her. He waves a wand, and says "You're a tree!" Endora turns herself into a tree, and the kids run away. She then turns herself into a young girl in a gypsy costume with a trick-or-treat bag. She knocks on the door and dislikes Darrin's candy, so she says she tricked him. "You'd better watch out," she says. Darrin obviously thinks she's just a little girl who can do no harm. But after she leaves, he suddenly has a scruffy beard. Outside, the trick-or-treaters are talking to the young Endora about the tree incident. Samantha has realized who the girl is, so she makes her come inside. The kids think they are fantastic costumes: "The little one was the mother!" Little Endora reveals that Darrin is going to be a werewolf.
Samantha asks Endora, still posing as a little girl, to remove the spell, but she says she can't remember it. Darrin keeps trying to shave the hair off his hands and feet, but it keeps growing back. When the guests arrive, he keeps leaving in order to shave. But soon he gets claws and fangs and it is no longer worth shaving. He escapes out the window until Endora can remember the spell. He goes into the backyard, but the moon is full, so he acts aggressively. Larry and the client are outside. When Darrin sees that they noticed him, he acts friendly. They take him inside to show the women the costume. When the client tugs his beard, Darrin growls, and Samantha explains it's a mouthpiece. Then he growls again and attacks a pillow. The client loves it. Darrin goes upstairs and locks himself in a closet. Samantha follows. Darrin apologizes to Endora, and she comes, an adult again, and takes the spell off. When Samantha realizes she knew the spell the whole time, she tells Endora she was acting like the stereotype witch, and did it to the only person who was willing to believe witches were different.
In the end, Endora meets the guests. The client says he likes Endora's costume and makeup, but of course she's dressed the way she normally does. "Happy Halloween," she says as they leave, and the client now has a tail.





