Charmed: The Power of Two

"The Power of Two" is the twentieth episode of season one of the television series Charmed. Directed by R.W. Ginty with a script written by Michael Perricone, it first aired on the WB Network on May 12th, 1999. In this episode, Elliot Spencer attempts to marry his beloved Allison Michaels, only to discover that his mother Grace made a pact with Hecate twenty years earlier, promising her child's offspring in exchange for wealth and power. The Charmed Ones learn of the debacle and do what they can to prevent the literal "Wedding from Hell".