Bewitched - Season 2 - Eps 29: Disappearing Samantha
The Stephens and the Tates go to a seminar where speaker Osgood Rightmire proclaims that witches do not exist. Samantha proves him wrong by setting up a few tricks for him, but he unknowingly gets her back by calling out a spell that makes her disappear and reappear voluntarily. Endora finds out that Osgood's power comes from a powerful ring on his finger. Endora grabs the ring and makes Samantha visible again.
About Bewitched

Title: Bewitched
First Air Date: 1964-09-17
Last Air Date: 1972-03-25
Status: Ended
Rating: 7.861/10 (from 695 votes)
Language: EN
Seasons: 8
Total Episodes: 254
Network: ABC
Genres: Sci-Fi & Fantasy, Comedy, Family, Drama
Production Companies: Columbia Pictures Television, Screen Gems
Synopsis
Samantha Stephens is a seemingly normal suburban housewife who also happens to be a genuine witch, with all the requisite magical powers. Her husband Darrin insists that Samantha keep her witchcraft under wraps, but situations invariably require her to indulge her powers while keeping her bothersome mother Endora at bay.
Cast

Elizabeth Montgomery
Samantha Stephens

Dick Sargent
Darrin Stephens

Agnes Moorehead
Endora

David White
Larry Tate