It s Christmas Eve. Kanuka's grandmother has gone missing. She leaves a note to Kanuka saying she is looking for the Christmas of 50 years ago. Fearing the worst, Noa, Asuma and Kanuka search for her, but are called back to duty to the SV2. Detective Matsui has asked the SV2 to help him on a case. Vehicles have been going into the Tokyo Port Tunnel but none have come out, including patrol cars. Also some is trying to disrupt communications around the area. Matsui wants the SV2 to do something before the military get involved. But the military have already been mobilized...