A dark alley in the city filled with old objects and skeletons connects the fragments of an unsolved case that has not been solved for twenty years - the chest of the first corpse is covered with yellowed photos, and the murder weapon is his mother's sewing machine; the death of the director of the orphanage looks like he was strangled by a childhood iron toy... Previous The captain of the crime team, Shen Yanbing, led Cheng Wu, a forensic doctor with a scar hidden under his eyepatch, Zhou Ye, an urban village hacker who is proficient in the dark web, and Lin Shuangjiang, an undercover detective who carries the secret of tattoos, to dismantle the murderer's "memory code" in the murder of old objects and mirror testimony.
The mastermind behind the scenes, the "pawnshop owner", appears in a bronze mask and uses "secret exchange secrets" to manipulate marginalized people such as scavengers and deaf-mute people to become scapegoats. The spearhead of all cases ultimately points to the foursome's childhood trauma: fragments of the pocket watch at the death scene of Shen Yanbing's father, drug-stained fingerprints from the arson case of Cheng Wu's mother, the strange connection between Zhou Ye's father and the old case, and the murder case behind Lin Shuangjiang's tattoo...
When the "life files" marked with the names of the four people were unearthed from the ruins of Bone Alley, and when scars similar to Shen Yanbing were revealed under the bronze masks, they had to face the cruelest truth - all the pursuit of murder was a confrontation with the dark alley of their own souls. The murder of old objects is the murderer's "memory tribute", and they have already become the priced "commodity" in this human experiment.
