Buried in the year-end rush but one of the year’s best films, Lee Chang-dong’s rending, hyperventilating follow-up to 2002’s Oasis focuses on Shin-ae (Jeon Do-yeon), a willowy, not-too-pretty young mother relocating to the obscure burg her dead husband came from, for obscure reasons. Reserved and cagey, Shin-ae herself remains a mystery, as she resists the gang-press of gossipy neighbors and over-friendly men (including congenial mechanic Song Kang-ho), plays with her headstrong grade-school son, and sets up a storefront piano school. Her unsettled life, and the mellow rhythms of the film, get scorched when her boy is kidnapped and then found dead, launching Shin-ae into a cascade of walking death, beatific Christian born-again-ness, leveling disillusionment (she decides to “forgive” the imprisoned killer in person, never a good idea), and self-destruction. Like a twisted sister to Rabbit Hole, Secret Sunshine doesn’t just posit grief but probes the hidden biology of it, like a parasite slowly chewing up its host from the inside. Lee makes lengthy, expansive, unpredictable movies always gripped by emotional tribulation, and the red-eyed Jeon, landing a Best Actress at Cannes in 2007 and unforgettable as well in The Housemaid, goes to hell and back.