Culwhich's attempt to join the ancient Master Madarian with the current Master was only partially successful. They are left to cope with two brilliant, devious minds trapped inside one body. Wendel discovers that Sapphire is on Earth along with the Masters. He is soon portaled to join her, along with Deadra, Jacob and Emily. Before they can find a way back to Mescalahem, Wendel and Sapphire are suddenly portaled to a mysterious, exotic land called Musterion. It is ruled by the powerful Empress Keres and her son Abdima. The Empress has devoted her long life to increasing her powers through the use of the forbidden dark arts. Not even Culwhich had achieved such terrible control over the powers of darkness. While on Musterion, Sapphire and Wendel go through a powerful, emotional fusion ritual together. They learn much more about who they truly are and what they are destined to be. In a thrilling out-of-body experience, their hearts and souls are joined together, which greatly enhances and expands their already formidable powers. Near the end of their joined fusion ritual, they learn that they will need all of their great powers and strength to deal with the terrible trials still to come. The powers of darkness are striving to bring the Empress and the newly joined Masters together to rule over Musterion and Mescalahem. Wendel and Sapphire are told they must stop this unholy union. They are warned that the Lost Continent of Musterion will be the final key to victory for one side or the other.