Shinichi has regained some semblance of a normal life. However, with Migi's cells dispersed throughout his body, his physical abilities have greatly increased to the point that not even Mitsuo poses a threat. Shinichi fears that the changes go beyond the physical and into the psychological. Just as peace returns to his school, a new parasite appears!

Though still full of doubt, Kuramori has, for the time being, accepted Shinichi. Soon after, Kuramori's resolve is severely shaken by witnessing a parasite murder a human being. Shinichi is frustrated by the turn of events, but the lull is cut short when a new parasite appears...