This surrealistic comedy follows the life of Haruo Maekawa, a young man who makes a living catching squid. Haruo is obsessed with catching a legendary giant squid rumored to live in Tokyo Bay. Haruo's uncle Takashi, fallen on hard times, comes to stay with his nephew until he can get back on his feet. Uncle Takashi is addicted to energy drinks, and seduces any woman in sight, including Haruo's girlfriend Rika. While praying at a Shintō shrine, Uncle Takashi is bitten in the scrotum by a poisonous snake and dies. The uncle is destined to spend the afterlife in Hell unless his nephew and girlfriend can rescue him from the King of Hell.

Sex Machine tells of the affable but simple Hiroshi, who during one sweltering summer in a small, parochial town, moves in with his girlfriend, Haruka. Their lovemaking is as athletic as it is bizarre but a dark storm comes looming when Haruka's ex boyfriend comes knocking at the door.