Ching-yi Fala Chen is a nurse who cannot sleep after her boyfriend Ho-hong Gordon Lam Ka-Tung leaves her and vanishes following a heated quarrel. To cope, she buys a pillow stuffed with aromatic herbs, and at last she drifts into sleep, only to wake inside a netherworld of dreams where she finds herself intimate with Ho-hong. The man in these dreams is not a comforting memory of her partner, but an incubus-like demon wearing his face, subtly draining her life force as the nights pass. With each use of the herbal pillow, her health declines—fatigue deepens, there are eerie sensations in her body, and a growing sense that something terrifying is siphoning her vitality. The truth surfaces in fragments: during the quarrel, she had accidentally stabbed Ho-hong in the neck and killed him. She cleaned the scene, vacuum-sealed the body, and hid it in the closet. When a mysterious tip-off leads security officers to force their way into the apartment, they find Ching-yi in critical condition, leaving a chilling implication that the demon’s influence may extend beyond the couple’s tragedy.
A separate thread follows a group of youngsters revisiting the abandoned old primary school from which they graduated. The building sits on the edge of demolition, its caretaker still living inside, but the students ignore the caretaker’s warnings to leave before dark. They engage in a variation of hide-and-seek that snakes through empty classrooms and shadowed corridors, and as night deepens, the ghosts haunting the campus begin to reveal themselves. The film builds to a haunting revelation: all the youngsters encountered that night were lost to the netherworld, and none of them survived the fateful game.
Meanwhile, Uncle Lam Teddy Robin—a short, elderly man carrying a black umbrella—traverses the streets at night during the Ghost Festival. For every good deed he performs, he carves a mark on the umbrella handle: saving a passerby from a bus, guiding police to a thug beating a man, and lecturing a young robber. His path collides with Jenny Aliza Mo, a prostitute who lures him to her apartment after feigning a sprained foot. When he declines her advances, she turns hostile and tries to extort money. She summons her bodyguard, who proves to be the thug Lam confronted earlier Kelvin Kwan. Cornered, Lam sheds his disguise and reveals his true nature as a demonic creature. In a brutal finale, he kills both Jenny and her ally and then devours Jenny’s innards, leaving onlookers shaken and the room looming with dread.
