Legend has it that after the ancient Emperor Zhuanxu died, the whereabouts of the divine sword he forged, Fenxu, became unknown. Jiachen, a death servant of the Yi Clan, was suddenly recalled during an investigation into strange happenings in Xuannan City to take part in a battle to exterminate a clan. Unfortunately, he was knocked unconscious by the aftershock of the Four Symbols Vajra Wheel shattering. When he awoke, he was told the secret of Fenxu's hiding place: it could be sensed by a branch of the Ling Clan, whose members even carried a self-immolation curse placed on them to protect the sword. To break the curse and find Fenxu, Jiachen disguised himself as Situ Xunkong, the lover in the memories of Ling Xueru, a survivor of the Ling Clan. Taking advantage of Ling Xueru's altered memories to gain her trust, he set off with her on a quest for the sword, where true and false memories became entwined with feelings both real and illusory.
