Eastbound Theatre, Milford: They say there’s a fine line between genius and insanity. In David Auburn’s Pulitzer Prize-winning play “Proof,” the saying reads true for Robert. He is a mathematical genius, who suffers from mental instability. The problem is that his daughter Catherine has inherited his brilliance and is worried about the prospect of inheriting his mental problems as well. Like a perfect mathematical equation, everything falls into place at Milford’s Eastbound Theatre with solid and memorable performances.

Directed with a perfectly balanced pace and what can only be heartfelt insight by director Ann Baker, the talented cast pulls out all the stops for this winning production. Each actor so embodies his/her character that the audience cheers for all of them at curtain call. Having seen this show multiple times at various theaters, both Equity and community theaters, this is by far the best rendering of all.

Peter Haynes has the perfect formula for playing Robert, the mathematical genius who mentally goes off center and the loving father to Catherine. Haynes knows just when to appear scholarly and brilliant and when to release paternal truthfulness and affection.

Amanda Piechota is the lead in the play and she is as elegant as she is eloquent. Her performance as the dutiful daughter who sacrifices her own college education in order to care for her father is most convincing because of Piechota’s sincerity. Mixed with just the right amount of subtlety and charm, this is one actress audiences will want to see again and again.

Glen Ghirardi delivers a performance so finely polished that of course he shines. Playing Hal, one of Robert’s graduate students, he hopes to discover some of Robert’s proofs after Robert’s demise to grant him entrance to any math school in the country. Ghirardi as Hal is both intelligent and smitten by Catherine. His attraction to his professor’s daughter is more than sexual but less than love. Yet Ghirardi manages to play this role so evenhandedly that he comes off honest and most likeable.

Taryn Chorney has one of the most challenging roles as Catherine’s no-nonsense sister, Claire. The role is challenging because she arrives after her father’s death, never having taken care of him and suddenly wanting to take care of Catherine by removing her from her present home to New York City to live with her. What works so well for Chorney are her compelling arguments that are so well delivered that the audience agrees with everything she says. Even when we don’t like her suggestions, they are so full of reason that we’re willing to accept them.

Overall, this is a dynamite cast delivering outstanding performances. Kevin Pelkey designed the set, though I still don’t know why people had to enter the house to exit the house. Donald Rowe’s lighting design worked well a did Jacquie Carlsen’s costume designs.

You don’t have to be a mathematician to enjoy this show. The production plays through Oct. 6. Box office: 203-878-6647.

Joanne Greco Rochman is an active member in the American Theatre Critics Association. She welcomes comments. Contact: jgrochman@gmail.com.