Edmund Charles Gruss (c. 1933) is Professor Emeritus at The Master's College in Santa Clarita, California and an author. He researches groups he considers to be "cults" and the occult and has written many books on those subjects especially on the Ouija Board and Jehovah's Witnesses.
Gruss was a member of the Jehovah's Witnesses from the age of seven to seventeen. He subsequently converted to evangelical Christianity after he "found Christ."