On the first day that trainee nurse Su Wanqing entered St. Mary Ann's Hospital, she was trapped in the eternity of three o'clock in the morning. The blood-stained nurse's watch, the clock tower rotating counterclockwise, and the skeletons nailed to crosses in the underground mass graves pushed her towards the death contract made a hundred years ago. The mysterious demon hunter Jiang Yimo appears with a cinnabar soul-locking bead, and the two are forced to form a blood pact to live and die together. However, they reveal a more horrifying truth - Su Wanqing was actually the last pure yin sacrifice sacrificed by the Hundred Ghosts in 1943, and Jiang Yimo's dragon and tiger tattoos are sealed with the sin of killing his loved ones with his own hands.
When the clock tower bell rang again, Yin soldiers pushed the ambulance full of ghost babies through the modern corridors, and antiseptic and corpse poison were mixed into a hallucinogenic mist. In order to break the curse of reincarnation, Su Wanqing must pierce the soul-locking bead into her heart with her own hands, while the restless remnant soul of her brother in Jiang Yimo's body is waiting to be reborn on the night of the blood moon. In this desperate game that spans time and space, the most dangerous thing is never the ghost, but the bloody hand that she still wants to hold tightly despite the pain.
