Forensic trace-evidence prodigy Shen Zhao returns to the field and joins forces with stubborn police captain Lu Tang to investigate the disappearance of a woman journalist, a case that has been buried for five years. From a stray fiber to an unusual leather impression, they peel away layers of disguise in the microscopic world. Lab technician Qiao Yan hides data, private detective Lin Xiu brings forward bloody evidence, and deputy director Zhou Mubai uses the dead as pawns to lay a deadly trap. When every drop of blood becomes a code, they must recover the victims' voices before the truth is buried forever.
