A night like any other in the streets of Hong Kong: in the midst of the tangle of night-owls, cars and vendors, a group of passengers climb aboard a minibus that is to take them from Mongkok to Tai Po. The group is as diverse as the city: there's a young man on drugs, an arguing couple, a woman with prayer beads and a girl who has just fallen in love, and behind the wheel sits the chatty driver. As the bus emerges from a tunnel, everything is suddenly quite still: the streets and buildings are all empty and there's not a soul to be seen; it's as if everyone has suddenly been swallowed by the earth. Only the millions of neon lights continue to blink, as if nothing has happened. The eclectic group of passengers seek refuge in a deserted café and discuss what they should do. Then they make a horrific discovery...