Mysterious mass disappearance of elementary school students in the mountains, save the bond between parent and child

A mysterious incident occurred in which 18 elementary school students suddenly disappeared in the mountains. Kitami of MER heads to the scene and decides to disperse the members in order to search for and treat the children. The members who have overcome the pinches as a team so far fight apart from eachother. While Otowa Nao and Tsurumaki Hina are struggling to treat the children who has an unexplained serious illness, Kitami desperately treats them but the medicine he has is not enough. The biggest crisis strikes Kitami.