A Watcher in the Attic (1993)

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.