a taut Korean thriller that leans into shamanistic and folkloric tradition

Sleep begins in the dead of the night, the opening credits roll accompanied only by the rhythmic sound of snoring. This sound is broken as a woman stirs to find her husband not beside her but sitting bolt upright on the end of the bed. As she turns on the light, he says in a deep and distant voice: “Someone’s inside.”

Jung Soo-jin (Jung Yu-mi) lives with her actor husband Oh Hyun-su (Lee Sun-kyun) and their dog Pepper in a typical, modern, urban Korean flat. The couple are expecting a baby and everything in their life seems to be perfectly normal – that is until this night. This eerie opening is Hyun-su’s first experience of parasomnia. He is talking and moving in his sleep with no memory of what he did when he wakes.

Sleep is the debut film from Korean director Jason Yu, a former assistant to the Oscar-winning director Bong Joon-ho (Parasite, 2019). Told in three chapters, it’s a thriller following this couple as they try to work out what is causing Hyun-su’s parasomnia. As these opening moments show, it might take more than some sleep strips or medication to help Hyun-su. There is something else in their flat going bump in the night.

Drawing on Korean folkloric tradition and cultural ideas around shamanism Sleep is a gripping, beautifully shot supernatural thriller. Yu’s debut brings to the screen a new kind of shamanism, a religion and part of Korean culture that has been ignored and suppressed for hundreds of years, but is reportedly being embraced by a new young generation of believers thanks to social media.

Chapter one shows the everyday life of the happily married couple. Yu paints a picture of wedded bliss through close-up shots that show a typical morning. The breakfast lovingly prepared by Hyun-su for Soo-jin before she wakes, the flowers on the balcony, a well-organised diary, a large framed photograph of the couple.

This sun-dappled montage ends on a large piece of wood with the words “Together We Can Overcome Anything” being righted on the wall by Soo-jin. This sentiment will become a recurrent theme throughout the film as Hyun-su’s parasomnia becomes more disturbing and threatens his safety (eating raw meat, attempting to jump from a window) as well as that of his whole family.

Soo-jin’s mother first suspects the supernatural might be responsible and suggests the couple seek a shaman’s help. Shamanism in Korea culture stretches back over 5,000 years. It’s found in the nation’s founding myth of Dangun, the first ruler of Gojoseon (the first Korean kingdom) and the son of the ruler of the heavens – a sort of Korean divine right of kings.

Shamanism in Korean film has a long history, with features such as Ieoh Island (1977) and The Wailing (2016) being among Korea’s best. It also featured in Exhuma, which was also released this year and presents young shamans as they try to rid a family of a curse. These films, however, portray shamanism as a provincial, rural concern. Sleep brings it into a modern and urban setting.

In Sleep, we are introduced to the shaman Madame Haegoong, who confirms someone is indeed inside Hyun-su. Koreans usually turn to shamans when they have problems or are experiencing trouble making decisions. A shaman has played the role of priest, healer and diviner throughout Korean history.

In most cases, shamans serve clients as communicators – a kind of intermediary between the client’s world and the other world where the spirits, the ghosts, reside. As a healer, the shaman usually performs a kut, an extravagant and expensive ritual, to enable connection with the spirit – an essential part of the treatment – as is the case of Hyun-su in Sleep.

In Sleep, the frustrated and sleepless Soo-jin is initially suspicious of shamanism but gets increasingly drawn in as medical avenues bear no results and Hyun-su’s behaviour becomes more dangerous.

In Soo-jin’s journey from non-believer to obsessive follower, familiar folkloric narratives associated with shamanistic belief arise. For instance, Soo-jin starts to believe her husband’s sleep problems are connected with ghosts latching on to him while he sleeps because, as Madame Haegoong explains, “the soul becomes more vulnerable and they exploit this to sneak into your body”.

Such narratives about death and spirits are typical in Korean culture. In the film, a now seemingly crazed Soo-jin explains: “If [your soul doesn’t] ascend in ten days you become a ghost,” and “A ghost cannot ascend 100 days after death. [It will] wander around our world forever.”

These ideas sound old-fashioned and ridiculous. However, that it’s a young woman being taken in by these ideas chimes with the recent reported interest in shamanistic belief among some South Korean youth. Some shamans have put this interest down to young people looking for hope and reassurance in the face of instability, much like Soo-jin.

Sleep is an expertly crafted modern occult film, featuring strong performances, including the posthumous leading man appearance from Lee Sun-kyun, who died by suicide last year. In his directorial debut, Yu has combined suspenseful horror and thriller with traditional folkloric shamanistic stories in an effective way.

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