After just starting at his new school, Mashio Gaku is suspended within a week for getting into a scuffle with a third year. After returning home to his disapproving dad's okonomiyaki joint, his father, Mashio Harumi, can't help but reprimand him and refuses to serve him. Their harsh words are the last exchange they share before an unfortunate traffic accident takes Harumi's life.

At his father's wake, Gaku finds out he was, in his words, a big fuckin' deal. In mourning, Gaku heads out to fish like him and his father always would, only to hook a big catch and get pulled into the water... When he comes to, he finds himself staring a familiar stranger in the face... in the year 2000.