Review of The Immortality Key: The Secret History of the Religion with No Name by Brian Muraresku, St. Martin’s Publishing Group, 2020, ISBN: 9781250207142 (hardcover), 460 pp, $20.63. Brain Muraresku is a practicing attorney and a student of ancient languages (Greek, Latin and Sanskrit), whose twelve-year odyssey through the archives of Western religion culminated in the publication of The Immortality Key (TIK). According to Muraresku, this work, which “presents the pagan continuity hypothesis with a psychedelic twist,” addresses two fundamental questions: “Before the rise of Christianity, did the Ancient Greeks consume a secret psychedelic sacrament during their most famous and well-attended religious rituals? Did the Ancient Greeks pass a version of their sacrament along to the earliest, Greekspeaking Christians, for whom the original Holy Communion or Eucharist was, in fact, a psychedelic Eucharist?” TIK will entice general readers but exasperate academics, even those who may agree with its specific conclusions regarding the role of entheogens in the Eleusinian Mysteries or early Christianity. Despite its popular appeal as a New York Times Bestseller, TIK fails to make a compelling case for its grand theory of the "pagan continuity hypothesis with a psychedelic twist" due to recurring overreach and historical distortion, failure to consider relevant research on shamanism and Christianity, and presentation of speculation as fact.