A Korean noir! We don't see too many of those. Netflix said I would like it. I'd previously seen The Host by the same director, didn't like it that much. But this one was more my speed.
Mother and her son, Yoon Do-joon, live in a small Korean village. She runs a small herb shop, and does unlicensed acupuncture on the side. She's very protective of her son, since Yoon Do-joon is operating with some pretty serious mental problems, a six-year-old brain in a young man's body. In addition to being stupid, he's impulsive, randy, occasionally violent, and has an extremely faulty memory.
But he seems to be muddling through OK, until a young girl turns up dead and Yoon Do-joon gets arrested for the crime. Mother denies his guilt and starts an investigation to find the real killuer and exonerate her son. She is extremely relentless, and also extremely inept. Nevertheless, she peels back the onion, layer by layer. Secrets are uncovered, not all to Mother's liking.
A little more arty than I thought it would be. A number of critics detected black humor; it must have been so black that I missed it totally. But I liked it OK, although it might not be your cup of kimchee.