>Haven't heard of this what is it about?

From TIFF's synopsis / notes:

Following the smash success of his 2006 film THE HOST, Korean sensation Bong Joon-ho returns with a stylish thriller that is both detective story and psychological horror. Pushing past the bounds of conventional film noir, Bong refines his talent for popular entertainment in MOTHER and crafts a new grammar of imagery to depict his disturbing yet always thought-provoking ideas.