The Hole
洞 (1999)

In the final days of the year 1999, almost everyone in Taiwan has died from a strange plague that ravished the island. Supposedly spread by cockroaches, the disease sends its victims into a psychosis where they act like the insects and eventually die. The two protagonists live In a crumbling apartment building right above and below each other. The woman is on the lower floor, and the pipes above her apartment are leaking fiercely, threatening to destroy her food supply, not to mention her sanity. She calls a plumber to go check it out, and he accidentally pokes a hole through the floor of the man's apartment. The two have never met before, and they come into contact through the hole.