In A Heart of Darkness Lies a Battle For This World and the Next. During a dark age of demons and ghosts, the Heian Emperor relies upon the imperial order of the Onmyoji to protect the kingdom. However, as the birth of the emperor's heir approaches, political intrigue and jealousy will lead to the most dangerous of betrayals-from within the Onmyoji and the Emperor's family! It will be up to the most talented of the order, Seimei, to face his master, Doson, and the dark magic that threatens to destroy them all! Onmyoji the movie is based on the famous serial novels set during the popular Heian period by author Baku Yumemakura. Theatrically released in Japan, October 2001, "Onmyoji played in over 2500 screens and grossed more than 3.1 billion Yen (approximately $23.6 million dollars).