First, the bad news: Cottage Theatre’s excellent production of David Auburn’s Pulitzer-winning drama Proof ends its run this weekend, so you’ll have to scramble to get tickets.

The good news, then, is that, should you land seats, you will be treated to one of the finest local productions of the year. Directed with a sure hand by Alan Beck and featuring a small cast of talented local actors, this production achieves an almost perfect balance of emotional resonance and technical finesse. The play is so engaging and moving, so rich and dynamic, it feels like a dream.

Proof tells the story of Catherine (Nicole Trobaugh), the 25-year-old daughter of Robert (Patrick Torelle), a mathematical genius, recently deceased, whose early promise was scuttled by serious mental illness. Having cared for her father at the expense of her own promising career in math, Catherine now wallows in depression and isolation.

Catherine’s solitude is broken by the arrival of her father’s former grad students, Hal (Kory Weimer), who scour the notes Robert left behind, in search of nuggets of genius. Further complicating matters is the arrival of her sister, Claire (Janet Whitlow), a high achiever who wants to haul her moping sister back to New York, where she can start a new life.

Set solely in the backyard of the family’s Chicago home, the play jumps back and forth in time, establishing at once the ravages of Robert’s insanity as well as the legacy of his tragic career on the surviving characters. Issues of genius and insanity, trust and love, self and world — the stuff of life — are complexly dealt with, though never at the expense of authentic human drama. Proof is a gritty, flesh-and-blood story that grapples big themes — it is at once ethereal and hyper-real.

What really makes this particular production great, however, are the performances, which are pitched one to the other like tuning forks, so expertly do they reveal the messy tangles of fate and human connection. Every actor here shines, but the star belongs to Trobaugh, whose portrayal of Catherine captures the heartbreak of a brilliant woman struggling — desperately, hopefully — to break free of her own demons.

Proof plays through June 28 at Cottage Theatre in Cottage Grove; tickets at cottagetheatre.org or 942-8001.