The question Korean director Jason Yu is asking in this eerie little spine-tingler (his debut feature) is “how well do you know your partner?” He may also be inquiring whether or not you believe in life after death, while planting nagging seeds of doubt about the competence of the medical profession.
A ride both disturbing and sometimes darkly comic, intensified by an edgy and neurotic soundtrack, Sleep has chosen for its claustrophobic battleground the apartment of married couple Hyun-su (Lee Sun-kyun, from the Oscar-blitzing Parasite, who shockingly killed himself last year) and his wife Soo-jin (Jung Yu-mi). He’s an aspiring actor and she’s an estate agent, but about to give birth to baby Ha-yoon.
However, their prospects for nuclear-family bliss come under pressure when Hyun-su begins to develop disturbing nocturnal symptoms. The first sign of trouble is when Soo-jin is woken by a loud bang in the night, then finds her husband sitting bolt upright in bed, intoning the words “Someone’s inside”. When she tries to speak to him, he slumps back in a deep sleep, having apparently been in a trance-like state. An alarmed Soo-jin makes a perimeter check of the apartment, but finds only a banging door, propped open by one of her husband’s sandals.
He’s perfectly fine in the morning, but this is only the beginning. A neighbour tells Soo-jin how she’s been hearing assorted strange noises from their apartment for days, and her spouse’s behaviour grows steadily more grotesque. One night he begins scratching obsessively at his face, and by the time morning breaks he has bloody gashes across his face and neck.
She finds him raiding the fridge, gulping down lumps of raw meat and fish (it’s a spectacle that makes her throw up). A visit to a specialist produces a diagnosis of an REM sleep disorder and a course of pills, but the doc’s bland assertions that Hyun-su’s condition is nothing to worry about become increasingly preposterous.
Nothing feels safe, and seasoned horror-watchers may feel some anxiety about the couple's cute little Pomeranian dog. Soo-jin becomes terrified that her husband might somehow harm the baby, and she ends up spending nights in the bath, clutching her infant desperately.
Director Yu’s cunning plan is to illustrate how the psychological balance in the couple’s relationship undergoes a metamorphosis under the strain of this inexplicable crisis, which is eating into their relationship like a steady drip of sulphuric acid. When he’s awake, Hyun-sun is the picture of amicable reasonableness, trying to reassure his wife that he’s getting better and everything’s fine. She, on the other hand, is steadily battening down the hatches and going into tiger-mom mode, ready to go to bat to destroy whatever it is that has invaded their household. When her mother brings in a shaman (or in this case sha-woman, should such a title exist) to take the psychic temperature of their home, it becomes clear that it’s a case of desperate times, desperate measures.
Yu steers his film deftly to a turbulent climax, though after all that’s gone before his conclusion feels a little too tidy, not quite the cathartic eruption that he seemed to be leading us towards. Leaving the viewer wracked by implication and ambiguity might have been a better bet than opening the envelope and waving the answer in our faces. It’s certainly worth 95 minutes of your time, though.
