An ordinary-looking but ambitious girl inadvertently signed an evil oath with the demon Belial. After she died in a strange accident, her soul moved into the body of Michael, the most beautiful of the seven archangels in heaven. The kingdom of heaven fell into chaos because of Michael's "loss of memory". The barrier of the gate of hell was opened, and the demon army took the opportunity to invade. At this time, Michael pretended to recover out of fear of being executed...