On a cold night when the city was closed in snow and wind, an unknown body was found with half an old photo stained with blood in its hand - the photo showed the backs of Lu Jihan and Xie Zhiheng standing side by side, but the two had clearly never known each other. Lu Jihan, a former criminal investigation consultant, retired due to an unjust case; Xie Zhiheng, the only survivor of a mysterious disappearance, has now become a wanted criminal. When the police forcibly connected the murder case with Xie Zhiheng's past, Lu Jihan found a pen buckle designed by himself between the fingernails of the corpse. When Leng Ye took his life, he realized that he was never truly alone, and Xie Zhiheng was the shadow who shouldered his sins.
