KARACHI: A mathematical genius and his daughter, their relationship both strained and necessary, and the discovery of a `paradigm-shifting proof` about prime numbers is the peg of the play Proof, part of Napa`s International Theatre and Music Festival, staged on Friday.

Part of a collaboration with the US, Proof, directed by Laquetta Carpenter, is set in Chicago and translated into Urdu. It explores the dynamics of sanity and insanity and the problem one faces with defining the parameters of both.

Catherine (Shabana Hassan), daughter of Robert (Owais Mangalwala), a mathematical genius known for his eccentric behaviour, is mourning the death of her father. The opening scene is on her birthday with her father walking in, and both celebrating the day with a bottle of champagne.

Simply executed in the living room of their house, the two talk about a variety of topics. Math is a constant thread in their exchange. There is also the fear of obscurity and of succumbing to madness. It is only in the midst of the conversation that Catherine talks about Robert`s death, an event that took place a week ago. She questions her father how despite his death he still stands before her. The exchange henceforth raises more questions than answering them. But it does setthe toneforthe restofthe play,0falurking darkness in the lives of the characters a darkness that is both literal and present in the recesses of their minds.

Hassan`s portrayal of Catherine is nuanced. There are moments when she internalises the grief and the relief she feels at her father`s death which is beautifully interpreted in her actions. Casting a lead female who is responsible for taking the entire play forth is a daunting task for an actor, and Hassan manages to pull off the role convincingly.

Her relationship with Hal (Kashif Hussain), an ex-student of her father, starts off on the wrong foot but they manage to find each other amidst their differences.

Hussain`s depiction of the shy and unsure Hal is awkward and clumsy, with an honesty that is charming.

Though both must be commended for their acting, it is unfortunate that they shine only in isolation but not when put together. At times the dialogue delivery suffers, with it coming off as stilted and terse, and even mechanical.

The first half of the play explores Catherine`s relationships. Her sister Claire (Sonia Ashraf) flies in from New York to attend her father`s funeral and we see a softening in her demeanour, which is further highlighted when Catherine falls for Hal.

Just when she feels like life is about to find its bearings, Catherine must once again grapple with her father`s work which she wants to forget, and prove the authorship of his work.