Proof is the powerful and compelling story of a young woman haunted by her father's legacy of genius, and madness. Catherine has spent years caring for her father, a celebrated mathematical genius whose life and career are cut short by mental illness. She struggles with the mathematical talent she has inherited from her father, as well as the possibility that she may be prone to his mental instability. The multiplicity of Proof is what makes the play so universally appealing. It's necessarily multi-layered because it deals fundamentally with what we choose to believe about ourselves and others, and what "proof" we have or feel we need in order to do so.