The industrial engineer divers who earn the money in the Otherworld and spend it in this world. We can find the pride of them who are professional of the professional divers in the logbook, a daily record of diving. They, passed the half of their life in the sea, have written everything down to the last detail in the logbook. They have lived by their own respective sea. But, since the spring of 2014, all their logbooks have begun to contain the same stories. The records are very short and desultory. What happened in the sea?