Forget what you've heard about Proof, which opened last night at the Walter Kerr Theatre, transferring to Broadway from an extended run at the Manhattan Theatre Club. It really has nothing to do with math at all, other than a few vague mathematical references tossed in to set the scene and establish the stakes, as it were. Anyone who can come close to balancing a checkbook already has more than sufficient knowledge to fully comprehend what's going on, on that side of the equation.

David Auburn has written a wonderfully compassionate and knowing play about a young woman, Catherine (Mary-Louise Parker) who, on the death of her father, must sort out and deal with a number of long denied feelings and fears. Catherine's father, Robert (Larry Bryggman), was a brilliant mathematician who crossed the thin line from genius to insanity several years earlier, leaving Catherine as his sole care giver for all her adult life. Now she must adjust not only to his death, but come to grips with her fear that his mathematical genius, which she has inherited, comes with a dreadful price, that she may be fated to the same mental degeneration and insanity as her father.

In a dazzling series of scenes, David Auburn gradually reveals and embellishes this situation, which is exacerbated by the presence of Catherine's older sister, the bossy and resentful Claire (Johanna Day) and Hal (Ben Shenkman), a former student of her father's who Catherine finds attractive, but who may only be out to further his own career. It's been a long time since Broadway has seen the debut of a new play the quality of Proof, and even longer since it has welcomed the debut of a new playwright as talented and promising as David Auburn.

Daniel Sullivan's direction is, in it's own way, as impressive as the play itself. Mr. Sullivan has blended the performance styles of four very talented actors into a deceptively smooth and ever evolving whole, much the same way a great conductor would shape and polish the performance of a great orchestra into something enchanting, seductive, and unique.

Mary-Louise Parker gives a finely nuanced performance, triumphing in an enigmatic, technically difficult role which would defeat a lesser actress. Johanna Day provides the perfect foil, trading on her character's familial rights with a brazen self-assurance which at first amuses, then terrifies. Both Larry Bryggman and Ben Shenkman repeatedly strike exactly the right notes as they redefine and embellish their individual relationships to meet the demands of quick pacing and situations which change from minute to minute.

Proof is a play you'll remember and which will haunt you forever.

Proof by David Auburn. Directed by Daniel Sullivan. Cast: Mary-Louise Parker, Larry Bryggman, Johanna Day, Ben Shenkman. Set design by John Lee Beatty. Costume design by Jess Goldstein. Lighting design by Pat Collins. Original music and sound design by John Gromada.

Theatre: Walter Kerr Theatre, 219 West 48th Street, between Broadway and 8th Avenue.

Running time: 2 hours with one 15 minute intermission.

Schedule: Tuesday through Saturday at 8 PM, Wednesday and Saturday at 2 PM, Sunday at 3 PM.

Audience: May be appropriate for children 4 and older. Children under 4 are not permitted in the theatre.

Ticket prices: $69 and $59 - Wednesday Matinee $65 and $54. The price will include an additional $1 Restoration charge, per ticket, for the restoration and preservation of the theatre. ($24/Wednesday Matinee $19 Balcony seating is available for purchase in person at the Box Office only.)

Tickets online: TeleCharge

Tickets by phone: TeleCharge at (212) 239-6200, or outside the New York metro area (800) 545-2559, 24 hours a day, 7 days a week.

Tickets in person: Box Office hours Monday through Saturday 10 AM to 8 PM, Sunday Noon to 6 PM.

Tickets by E-mail: tickets@telecharge.com

Tickets by Snail mail: Proof, PO Box 998, Times Square Station, New York, NY 10108-0998. Note: Mail orders must include the $1 Theatre Restoration charge for each ticket.