David Auburn’s Proof concerns math and mathematicians, but is better described as a play about the complexities of passion and unfathomable intelligence. Here, math may stand in for any pursuit that's demanding and precise and beautifully rewarding for those who pursue it enough. The play is also, in no small part, about human interaction, obligation, ownership, and mental illness. Director Suzi Regan helms a production well worthy of this dense, masterfully efficient script in a hard-hitting two hours at Tipping Point Theatre.

Fittingly, the story begins with guarded Catherine (Kate Peckham) and her father, storied math legend and University of Chicago professor Robert (Hugh Maguire), gingerly talking about the trappings of sanity. The conversation heaps on layers of context when the characters quickly reveal that Robert has recently died, having grappled with career-ending insanity for years under Catherine’s watchful care; the questions this interaction raises about her own mental state are not lost on either of them. Also within Catherine’s orbit are the alive and present Hal (Chris Korte), a young member of the math faculty warily permitted to scour Robert’s notebooks, and Claire (Kelly Komlen), her take-charge, put-together sister who swoops in from New York to remove Catherine from the dilapidated house of their childhood. The first act progresses in a linear fashion, before and then after the funeral, exposition spread thick in this slice-of-life approach that begins to twine the three living characters’ lives together. It’s all building toward a reveal changes the game entirely with one jaw-dropping utterance.

Auburn weaves flashbacks into his second act, delivering on the promise of the first-act recollections and showing the devolution of Robert’s mental health and the genesis of his dependence on Catherine. Maguire’s treatment of the delusional, damaged genius is superb, going from pathetic to frightful as he loses control. These developments cause Komlen’s present-day concern and motivations to fall into place, and her controlled character’s bafflement and frustration belie a real fear of helplessness that reflects on her absence in Robert’s last years. Korte does his best work opposite Peckham, advancing and receding in her favor, but always pushing for connection with nerdy earnestness and hesitant affection. However, it’s Peckham’s Catherine at the center of the play, and the actor is note perfect: introspection constantly plays across her face as she wonders how like her father she’s destined to be, both in ability and in mental faculty. It’s the viewer’s job to catch up with her speeding intellectual agility and come to better appreciate the source and depth of her protective, defensive behavior.

Scenes past and present unfold on Robert and Catherine’s dessicated back porch, which designer Monika Essen has craftily made to look like a decades-old bona fide fire hazard (with intricate kindling assists by properties designer James Kuhl and assistant Samantha Lowry). Daniel C. Walker’s lighting has a subtle hand as it plays with time, in terms of both the hour and the season. Sound design by Julia Garlotte sets the tone and maintains it through a mind-bending intermission — this is a show dead set on taking hold of the viewer’s thoughts and emotions and not letting up on either.

Regan’s animated staging makes it easy to forget the challenges of performing in the round; choices seem organic rather than deliberate, putting focus on the characters and story instead of the nuts and bolts of a live performance. The stage setup isn’t a universally perfect match for the space — the porch’s unattached symmetry doesn’t readily cement the difference between coming and going as characters drift on from one side and off the other, sapping some feel of ownership of the domain; moreover, the painstakingly stylized movement between scenes solves some transition problems but feels extraneous in contrast to the stark realism of the main action. Even so, these issues take nothing away from what happens on the porch in the moment, at times thought-provoking, at others wrenching, but consistently intense. With a powerhouse cast and keen direction, this deeply affecting Proof is a double-sided coin of promise and peril.