Emily Bergl and Sean Hayes Photo by Joan Marcus

Levant was, to say the least, a complicated person. For some, he is best known as a friend and musical interpreter of composer George Gershwin who, though long dead, plays a significant role in Good Night, Oscar. Others might recognize Levant from his appearances in such musical films as An American in Paris or The Band Wagon. Still others might remember him from his frequent guest spots on television's "The Tonight Show," hosted from 1957 to 1962 (the play takes place in 1958) by Jack Paar. Ben Rappaport is terrific as the boundary-breaking host who loved nothing more than a controversial guest to shake up his audience and rattle the network.

Sean Hayes' brilliant performance captures with near perfection the character of Levant, a man of great intelligence known for his seemingly spontaneous Oscar Wilde-like witticisms, many of them aimed at himself. For example, when asked by Paar what he does for exercise, he responds "I stumble, then I fall into a coma." Funny enough as a tossed-off line, but not entirely without an underlying element of truth. For Levant was quite visibly a bundle of twitches, tics and mannerisms that colored his brilliance with an air of scary unpredictability. You never knew what he might say or do, or even if he would make it through an interview.

Like the man he portrays, Hayes dominates every scene he is in. You dare not take your eyes off him for a second, especially when you learn Levant is only on hand at NBC Studios in Burbank, California, because his wife June (Emily Bergl, giving an equally commanding performance) has wrangled a four-hour pass from the psychiatric hospital where she had him committed after a manic and violent episode at their home.

Ben Rappaport and Sean Hayes Photo by Joan Marcus

Also on hand is Max (a delightfully nerdy Alex Wyse), Jack Paar's young production assistant who is in awe of every guest on the show. Because Max has done his fandom homework, his gushing declarations and encyclopedic knowledge provide a perfect vehicle for the playwright to provide us with much of the biographical information about Levant without awkwardly stopping the play's forward momentum. By the time Levant is ready to go on the air, we are well prepared to embrace the public side of the celebrated genius. We've also been set up by the nervous appearances by Bob Sarnoff (Peter Grosz), NBC's head honcho, who keeps warning Paar to keep his guest under control. No jokes about politics, religion or sex. Uh huh!

One of the play's many strengths is the way everything builds up to the live on-air interplay between Paar and Levant, both of them smoking cigarettes as they swap one-liners, or, more often, as Paar plays the straight man to Levant. Paar: "What have you been doing with yourself lately?" Levant: "I'm in the middle of a breakdown. It's my fifth in two years." Paar: "I'm sorry to hear it." Levant: "Don't be. That's the thing about schizophrenia. It beats dining alone."

Following the interview portion of the TV show, for which we serve as the studio audience, Paar sets us up for the one thing he knows will keep him out of trouble with the network. He announces that Levant will play the piano for us. During the commercial break, Levant spins off into another near-breakdown, during which he has a vision of George Gershwin (John Zdrojeski) demanding that he perform "Rhapsody in Blue," a piece of music he has been trying to escape from for many years.

Finally, though, when Levant capitulates, it is Sean Hayes, a thrilling pianist in his own right, whose performance we get to hear. And it is doozy, a furious rendition of "Rhapsody in Blue" that seems to be drawn from the same well that led to a defining moment in the film Shine, about pianist David Helfgott's mental breakdown, which featured an explosive interpretation of Rachmaninov's third piano concerto.

There is a perhaps overused but most apt phrase to describe what is happening on stage at the Belasco, and that is "tour de force." Garlands all around for playwright Doug Wright, the wonderful cast, director Lisa Peterson, and, especially, for Sean Hayes, for whom this is a career-crowning achievement.