Same as the "DCU (DeepCrimeUnit)" specialization in the underwater organization "DCU (DeepCrimeUnit)" and the stage of the オリジナルドラマ.ドラマのstage となるのは, coast guard 庁に newly established されたDCU というUnderwater incident やaccident のinvestigation を行 うスペシャリストCollection. DCU's abbreviation for DeepCrimeUnit (Special Diving Unit), its mission, and the police's role in sea waters It is difficult to find out the problem of "dangerous rivers and lakes all over Japan", and it is a submersible in the water. It proves that the incident is solved. "Unresolved Incidents in the Water" すること"が、　　のミッションだ.