The film is a film version of the 2016 Korean drama "Signal", which is a Japanese drama of the same name. In Tokyo in 2021, a senior government official died in a traffic accident caused by a rental car that lost control on the highway. The long-unsolved case investigation team led by Sakurai, headed by Saegusa, suspected that the incident was carefully planned. In 2009, there was also an incident in Tokyo where government officials died in traffic accidents one after another. At that time, the police announced it as an accident, and only Oyama doubted the true nature of the incident. At 23:23, the wireless communication machine that could not be connected rang again! In order to save Japan, which may be threatened by biological terrorism, the "present" and "past" events are involved in a deeper conspiracy. And can Saegusa and Sakurai successfully meet Oyama in the present?