The daughter of a brilliant mathematician must convince her new beau and her domineering sister that she wrote an important mathematical document. We don't care about the proof, the film's main source of conflict; director John Madden knows few in the audience are smart enough to care about theoretical math and physics. So what's left? Proof has to compel us with the interpersonal drama Catherine's relationship with her dead father and her sister and boyfriend who grow to doubt her sanity. But from very early on, we know there's no reason to doubt Catherine, so we're left waiting for the film to catch up to the audience, and thus the film loses its reason to compel us to care about these characters. Gwyneth Paltrow, who conjures her Sylvia character in her depressive moments, occasionally gives us reason to pay attention to Catherine's struggles, but especially when she raises her voice, Catherine, in Paltrow's hands, comes off as annoyingly disinterested and unengaged with manic bouts of petulance. It's hard to like Paltrow, and it's even harder to be interested in Catherine. Overall, I found Proof to be structurally flawed, and the film's star certainly didn't shine.