Lin Ye's life revolved around the gears and passing hours of his watch repair shop, until the brass master lock left behind by his grandfather began to glow faintly, revealing a secret buried deep beneath Yong'an Street. A fire twenty-five years ago not only destroyed the old house, but also sealed away a shadow that devoured lives. The gear-shaped mark appearing on his palm is the key to confronting it.
From Su Wan, who was dragged into the affair against her will, to his boisterous childhood friend Wang Dazhuang, who always steps up at crucial moments, the three young people face one strange encounter after another as they search for the truth: fragments of a sinister shadow, howls from beneath the foundations, and a mysterious person knocking at the door in the dead of night. When Boss Chen, sporting gold-rimmed glasses, appears with an identical brass box, and the demolition crew's machines grind across the ruins of Yong'an Street, they realize that the fire never went out. It merely changed form, waiting for desire to fuel it until it could devour everything.
This is a race against time, a struggle to fight the abyss with the mark in their blood. As the watch shop's pendulum resonates with the heartbeat beneath the foundations, they must piece together the truth torn apart by time before the shadow breaks free, and wind fate's gears once more with courage, for Yong'an Street's past and for their own future.
