Suddenly in the Dark (1981)

Immersed in a world of butterflies, affluent biology professor Kang Yu-jin welcomes a new addition to his household, the young and enigmatic housemaid, Mi-ok. A shaman priestess's daughter, Mi-ok carries the weight of her mother's untimely demise in a house fire. Initially, Yu-jin and his wife, Seon-hee, open their home and hearts to Mi-ok, but a peculiar wooden doll that she possesses stirs unrest in their tranquil life. Seon-hee, haunted by uncanny nightmares featuring an identical doll, grows increasingly wary of Mi-ok, suspecting a sinister plot to usurp her place and extinguish her life. In a chilling peak of paranoia, Seon-hee's actions lead to Mi-ok's tragic downfall. What follows is a relentless haunting as Seon-hee finds herself tormented by terrifying visions of the wooden doll, a menacing reminder of her actions, relentlessly pursuing her.

Suddenly in the Dark is a drama movie directed by Go Yeong-nam.

Suddenly in the Dark is currently streaming for free (ad-supported) on Freevee, KoreaOnDemand and Tubi TV.

It is also possible to buy Suddenly in the Dark on Amazon Video.