Hiroki Sakai adjusts pins in pachinko machines for a living. It's a dull existence, but Sakai seems to have made his peace with it. One day he runs into his former co-worker, Mizuguchi, a twitchy sort who managed a parlor before yakuza goons beat him up and robbed the place. Now he is obsessed with the thought of vengeance against his assailants. Soon afterward, he runs into Rie -- the daughter of his boss - who has suddenly blossomed into voluptuous womanhood and who is eagerly hoping to improve her relationship with Sakai. Later, he finds himself the target of yakuza aggression when the gang's boss comes to believe that Sakai is the bearer of a coveted envelope. Though a sensible and retiring sort by nature, he realizes that the only way to end this unwanted adventure is to rescue his boss, Tsumura, from the clutches of the yakuza.