One day, Sousuke Yamada, who has an elementary school daughter, stumbles upon a video of someone who seems to be his wife exposing herself in a sexual act on a secret account. What's more, the video was taken at the elementary school his daughter attends. Sousuke, whose heart is broken by his beloved wife's infidelity, vows to take revenge on the other man. The candidates for the other man are five fathers who are members of the PTA. Will he be able to find out who his wife's lover is in the PTA, where infidelity is rife?