Pathologist Fujimaki stumbles upon an unknown killer virus named "Gift" following a patient's death. Individuals succumb shortly after the virus infiltrates their bodies, leaving no trace behind and enabling a flawless crime. Greedy and influential individuals seek to exploit "Gift" to eliminate rivals or amass wealth. Fujimaki's life undergoes a radical transformation with the discovery of this dreadful virus. The real culprit behind introducing the virus into the hospital and orchestrating the serial murders remains a mystery.