Conspiracy is the fourth studio album by King Diamond, being the second part of a story that began on the album "Them". It was released in 1989. The song "Cremation" appears in the 2009 video gameBrütal Legend. Conspiracy is the last album to feature drummer Mikkey Dee who left the group but recorded the album as a session member.
In this sequel to "Them", an adult King returns to the House of Amon to reclaim his rightful place as heir to the house. However, unanswered questions about his sister's death, his mother's involvement with his diabolical therapist, and his own madness all prove to be difficult if not insurmountable obstacles.
He makes a deal with "Them" (the unseen antagonists from the album of the same name, part one of the story) to return control of the house to Them in exchange for the chance to see his now-dead sister Missy again. He believes she can help answer some of his questions. An agreement is reached, and Missy returns from the grave nightly to help King uncover some of the mysteries from "Them". As a spirit, however, she cannot save him from the plot against him, try as she may to warn him. His mother and his doctor have conspired to get rid of him permanently in order to inherit the house themselves. While they think they are ultimately successful, the album closes with King's promise to torture and haunt them forever from beyond the grave.