“First Lady Suite,” a musical by Chautauqua native and Broadway composer Michael John LaChiusa, about exactly what its title suggests, is a unique musical. It is bold, original, weird, abstract, daring, crazy and unconventional – in the right and wrong ways. Spend some time with it, stew in its uniqueness, and you’ll be rewarded with a rare experience.

A production of LaChiusa’s musical is now on stage at American Repertory Theater, where LaChiusa’s brother Matthew is artistic and executive director. He also directs this production, which bodes well for each brother. Here is material into which Matthew can dig his eccentric, sometimes erratic, chops. It works.

This is a chamber musical, a format that has been improperly marketed on other local stages, confused simply for “small” theater. A true chamber musical implies an intimacy with material, though, and not just the bodies on stage or square footage. Traditional musical structures can go poetic in a chamber structure, leaving you to weave together your own interpretation of material and form. When done right, it will appear sparse but finish full-bodied.

LaChiusa’s libretto lives up to all these wild ideals of the chamber format. His score flows freely from Gershwin to Sondheim to Philip Glass to even William Finn, relying on their proven textures while refusing to mimic them. It’s quite a feat, especially considering that it’s played – masterfully, easily, it would sound – on an electric keyboard by music director Michael Hake, whose passion for musicianship imbues every sound we hear. His astute touch is obvious in the exquisite solos and vocal blending of his six-women ensemble.

Scenes float between everyday portraits of four first ladies: Jacqueline Bouvier Kennedy, Mamie Eisenhower, Bess Truman and Eleanor Roosevelt. LaChiusa bookends these with an anthem that encapsulates the trying, triumphant lives they led. The prologue and epilogue, while musically beautiful, are the only structurally weak parts of this show, however mesmerizing the effects. The pageantry of it all belies the candid revelations these four scenes depict. Then again, these are some pretty odd scenes.

In a quaint scene between two of Kennedy’s personal secretaries, actress Mary Ryan shows the innate insecurity that comes with working for a woman who appears less than personal with her staff. The scene is set aboard Air Force One on its way to Dallas on Nov. 22, 1963. Ryan takes the nervous Mary Gallagher to a zany place but reins in her paranoid fear, internalizing it instead of going full-on Carol Burnett. Eager for an issueless interaction with her boss, she drifts off into a dream sequence in which she dissects the first lady’s obvious insecurities.

It’s a fascinating angle to explore a woman we all think we know, or wish we had. But this segment feels the most “West Wing”-like, where we see the first family through the staff’s eyes more often than its own. It is an odd perspective, as we have little reason to care about Gallagher, especially where her neuroses are concerned.

Yet Ryan, in the first of two extraordinary performances, is nothing short of breathtaking. Her range is versatile, her presence is enigmatic and her technique – both vocal, which is classical, and physical, which is comedic – is incredible. She sets the bar sky-high for her fellow actors.

Katie McMahon, as Mamie, hits many strong notes, too. Her scene, which characterizes Mamie as some sort of prime-time variety show host, shows a manic depression characteristic of many first ladies’ accounts of the presidential experience. With their husbands busy running the country, traveling the globe and fighting (or waging) wars, their families’ domestic lives get put on hold, in the country’s most beautiful domestic retreat, no less. No wonder Mamie is bouncing off the walls like a zoo animal.

McMahon is fresh and on her toes as the jubilant-by-way-of-insane Mamie, and holds her own in a scene that unfolds like an “I Love Lucy” episode. McMahon, though, brings some distraction to her wonderful work by failing to hold substantial eye contact with her scene partners, which translates back to our desire to focus on her. It’s the only detail of McMahon’s performance that’s inconsistent with an otherwise whimsical, if not disconcerting, portrait.

Shayna Raichilson-Zadok is especially captivating in a fantasy scene among Eleanor Roosevelt, Amelia Earhart and journalist Lorena Hickok, long assumed to be Eleanor Roosevelt’s lover. Raichilson-Zadok commands a jealous, frustrated Hickok with searing, intense vocals.

Here – and in every scene in which Marian Anderson unleashes her operatic prowess – LaChiusa paints fascinating new portraits of these censored, frustrated housewives; women who might only be able to hum their way through life.

In doing that, he frees the fractured, pained, defiant opera singers hiding inside.

Theater Review

“First Lady Suite”

Three and one half stars (Out of four)

Presented by the American Repertory Theater of WNY through March 16 at 16 Linwood Ave. Tickets are $20 general, $15 student or military veteran. For information, call 634 -1102.