Ryōko and Izumida investigate a former Health, Labour and Welfare minister due to illegal human experimentation of human cells with cells from an unknown human species, which resulted in a monster-like infant. The two officers try to eliminate the creature before they decided to let it die due to rapid cell degeneration.
涼子は、国会議員でありDK製薬会長の桂川平蔵にアポなしの面会を申し込み、一度は断られたが「54121」と呟くと許可される。その数字は、DK製薬が進めてきた違法の細胞実験のプロジェクトナンバーだった。