
Proof
A former student (Jake Gyllenhaal) of a recently deceased, brilliant mathematician (Anthony Hopkins) sleeps with the mathematician's daughter Catherine who has been caring for her ill father. She gives him a key, and he finds a notebook containing a proof of an important theorem which Catherine (Gwyneth Paltrow) claims is hers. The ensuing dispute is complicated by the arrival of Catherine's sister from New York and signs of inherited mental illness.