Ryōko nearly survives an assassination attempt with the assassin sacrificing herself by ingesting a suicide pill that made her combust. She and Izumida continue to investigate, with their case getting complicated when a forensics scientist the two officers knew for a long time is the leader of the cult and that they had been using growth hormones to make an ordinary snake grow large.
ミイラ化事件の原因は、毒物の混入された輸入食材によることが判明。さらに曽我がその検疫を行った「検研」の会長であること、月読会の幹部であることも分かった。そんな矢先に司法解剖を担当した研究所が燃え…。
