Plot

The landlord of a boarding house in 1923 Tokyo, is keen on spying on the bizarre close encounters taking place beneath his roof. One day he sees a prostitute killing a customer, and decides he's found his soulmate.

In 1923, in a cheap Tokyo rooming house, a languid young man named Goda was feeling bored with his life. One day while playing dress up with a woman's wig and lipstick, he accidentally loosens a ceiling board in his closet. Climbing up, he discovers a dimly lit passageway under the roof leading to the resident's other rooms. Soon he is scampering about like a ninja, making knotholes and moving ceiling boards for a better view. What he sees are the intimate acts - sadistic, criminal or vaguely mad - that reveal infinitely more about his fellow roomers than the various fronts they present to the world.

The story begins with residents of the Toeikan, a cheap Tokyo rooming house, drinking sake and discussing the impact sound will have on the movies. One, a languid young man named Goda (Mikami Hiroshi), sits apart from the others, blowing smoke rings and thinking how stupendously boring these people are - they don't have an original thought between them! Better to die and be done with it! Rather than end it all, however Goda finds a new interest. One day while he is playing dress up with a woman's wig and lipstick, he accidentally loosens a ceiling board in his closet. Climbing up, he discovers a dimly lit passage way under the roof leading to the Toeikan's other rooms. Soon he is scampering about like a ninja, making knotholes and moving ceiling boards for a better view. What he sees are the intimate acts - sadistic, criminal or vaguely mad - that reveal infinitely more about his fellow roomers than the various fronts they present to the world. As the days pass, the keen delight Goda first felt from his explorations begins to fade. He needs a new stimulus. He remembers Endo the dentist (Mutaka Naomasa), a loathsome toad of a man who once boasted to all and sundry of attempting 'love suicide' with the young wife of a colleague. Flashing a bottle of morphine, he told Goda and the others that "with this you can die easily and painlessly" Goda decides to steal the morphine and give Dr. Endo a taste of his own medicine. He plots his crime with an ingenuity worthy of an Arthur Conan Doyle villain, but has to contend with a lantern-jawed "researcher of human psychology" named Akechi Kogoro (Shimada Kyusaku), who takes a disturbingly keen interest in his fellow roomers.