Opening as tumultuous slapstick, this tale of a 27-year-old village idiot, Do-joon, and the local madwoman who is his single parent, Hye-ja, quickly darkens once someone bludgeons a schoolgirl. Do-joon is accused of her murder and easily confused into signing a confession. With the simpleton packed off to prison, Hye-ja's hyper-aroused maternal instincts drive the movie. She campaigns for her child's release and attempts to pin the murder on Do-joon's only friend. There may be no lengths to which Hye-ja won't go to establish Do-joon's innocence. Though he might indeed be innocent, the mother-son dyad is founded on its own guilty secrets. The two share a bed, and Hye-ja shows a marked interest in her son's virility. While in jail, Do-joon has time to think about the past. Rather than provide the evidence Hye-ja hopes for, he confronts her with a recovered memory that allows the movie to pivot into psychological drama. It would hardly be surprising if Hollywood attempted a remake — although it will be a rare studio movie with the nerve to re-create Mother's final reel, an ending that leaves its protagonist stranded in a moral netherworld, applying her acupuncture needle to the spot that "unknots the heart."