Catherine had cared for her father through a lengthy mental illness. Upon Robert’s (her father) death, his ex-graduate student Hal discovers a paradigmshifting proof about prime numbers in Robert’s office. The title refers both to that proof and to the play’s central question: Can Catherine prove the proof’s authorship? Along with demonstrating the proof’s authenticity, the daughter also finds herself in a relationship with 28-year-old Hal. Throughout, the play explores Catherine’s fear of following in her father’s footsteps, both mathematically and mentally and her desperate attempts to stay in control.

Proof is presented by special arrangement with Dramatists Play Service, Inc., New York.