Although the musical based on the 1975 film documentary of the same name had a sold-out, extended spring run at Playwrights Horizons Off-Broadway, it's still accurate to call the work "new": Librettist Doug Wright, lyricist Michael Korie and composer Scott Frankel, along with director Michael Greif, used the summer to sharpen their storytelling.

Korie told Playbill.com that five songs were cut and several new songs were written and inserted into the show in recent months.

Broadway previews began Oct. 3, introducing audiences — or re-introducing those who know the film — to the indelible real-life society women Edith Bouvier Beale and her daughter, Edie Beale.

The respective aunt and cousin of Jacqueline Bouvier Kennedy Onassis lived in squalor in a dilapidated 28-room mansion in Easthampton, Long Island in the 1970s. Their downfall made national headlines, and they became cult celebrities with the release of "Grey Gardens," the Maysles brothers' film.

The musical stroll through the American dream — the path of which is spiked with emotional poison ivy — earned rapturous reviews and a handful of awards for Christine Ebersole, who played (and still does) dual roles ("Big Edie" in Act One, and "Little Edie" in Act Two). Conventional wisdom is that the 2007 Best Actress (Musical) Tony Award is all hers, unless a wind from the east rattles the branches of Grey Gardens. Erin Davie makes her Broadway debut as young socialite Edie Beale in the new American musical. Davie, who appeared in the national tours of Swing! and The Music of Andrew Lloyd Webber, is, along with Ebersole, central to the stylish first act of Grey Gardens.

Set in 1941, Act One shows a momentous day in the life of Young "Little" Edie Beale, who is about to start a future with young Joe Kennedy, Jr. (The engagement party plot was constructed by the writers as a fictional focusing point for the show.)

In the first half of Grey Gardens, Christine Ebersole plays Little Edie's vivacious, controlling, spotlight-hungry mother, Edith Bouvier Beale. By Act Two, it's 1973 and their lives at the family's ramshackle Long Island mansion, Grey Gardens, have deteriorated.

By the second act, Ebersole assumes the part of fiftysomething Little Edie (Davie appears only fleetingly as young Edie), and Mary Louise Wilson plays the haggard Edith — alone together and haunted by the past.

The performances were hailed for their faithfulness to the quirks and voicing of the real-life women, whose eccentricities were captured in the documentary film.

"The events of the play," according to the earlier Off-Broadway Playbill note for the musical, "are based on both fact and fiction."

It was Frankel's idea that the film might inspire a musical.

The 1975 documentary picture remains a creepy account of mental, physical and social decline.

Here's how the producers characterize the show: "Grey Gardens brings to life both the delightfully eccentric aunt and cousin of Jacqueline Kennedy Onassis. Once among the brightest names in the pre-Camelot social register, these two women became East Hampton's most notorious recluses, living in a dilapidated 28-room mansion. Set in two eras — in 1941 when the estate was in its prime and in 1973 when it was reduced to squalor — the musical tells the alternately hilarious and heartbreaking story of two indomitable individuals, Edith Bouvier Beale and her adult daughter 'Little' Edie."

For the musical, librettist Wright borrows lines from the documentary to pepper an imagined Act One that has the whiff of Cole Porter's "High Society" to it. Act Two is set in the crumbling East Hampton home and more closely follows the documentary (including the more memorable lines from the ladies), spiked with songs, such as Frankel and Korie's haunting "Another Winter in a Summer Town."

Repeating their performances from last spring's Playwrights Horizons production are five-time Tony Award nominee John McMartin (Follies, Show Boat, Into the Woods) as Major Bouvier; two-time Tony Award nominee Bob Stillman (Dirty Blonde, Grand Hotel) as Gould; Matt Cavenaugh (Urban Cowboy, national tour of Thoroughly Modern Millie) as both Joe Kennedy, Jr. and slacker Jerry; Obie Award winner Michael Potts (Lennon) as Brooks; and Sarah Hyland (title role in Paper Mill Playhouse's Annie) as Young Jacqueline Bouvier.

Joining the company are nine-year-old Kelsey Fowler as Young Lee Bouvier. Audrey Twitchell, the young actress who created the part earlier this year, has outgrown it, physically. For the record, Sara Gettelfinger (Nine, Dirty Rotten Scoundrels) created the role of Young Little Edie Off-Broadway and is heard on the world premiere recording from PS Classics.

Producers of the Broadway production are East of Doheny, Staunch Entertainment, Randall L. Wreghitt/Mort Swinsky, Michael Alden and Edwin W. Schloss, in association with Playwrights Horizons.

Based on the cult-hit 1975 documentary "Grey Gardens" by David Maysles, Albert Maysles, Ellen Hovde, Muffie Meyer & Susan Froemke (a Maysles Brothers Films Inc. Production), the musical is directed by Michael Greif (Rent) and features musical staging by Tony Award nominee Jeff Calhoun (Big River, Grease!).

The Broadway production reunites the original creative and design team, featuring scenic design by Allen Moyer, costume design by five-time Tony Award winner William Ivey Long, lighting design by Tony Award winner Peter Kaczorowski, sound design by Brian Ronan and projections by Wendall K. Harrington. Orchestrations are by Tony Award winner Bruce Coughlin and music director is Lawrence Yurman.

*

The musical Grey Gardens is part of a flood of renewed interest in the Beales. There is a new Maysles Brothers companion movie, "The Beales of Grey Gardens" (featuring previously-unseen outtakes from the original documentary), several upcoming books (including a collection of Edie's original poetry) and a future Hollywood feature based on the documentary, which is now in pre-production.

Grey Gardens had its world premiere at Playwrights Horizons, opening March 7, 2006 and completely sold out its initial limited engagement as well as three extensions. The musical was named Outstanding Off-Broadway Musical by the Outer Critics Circle Awards and was also the winner of a 2006 Richard Rodgers Production Award, administered by the American Academy of Arts and Letters.

It was most recently honored by the theatre annual Best Plays as one of the 10 best of the 2005-2006 season, and the only musical cited.

For her work in Grey Gardens in spring 2006, Ebersole won a Drama Desk Award, an Outer Critics Circle Award, an Obie, a special citation from the New York Drama Critics Circle and the Drama League's 2006 Distinguished Performance of the Year Award.

Wilson earned Drama Desk, Outer Critics Circle and Lortel nominations and has been honored by the Drama League for her performance.

The world premiere recording, featuring the Off-Broadway cast, was released on the PS Classics label, although, as mentioned above, a handful of recorded numbers ("Toyland," "Body Beautiful Beale," "Better Fall Out of Love," "Being Bouvier," "Tomorrow's Woman") no longer are in the show. For more information, visit www.psclassics.com.

Tony Award winner and Pulitzer Prize winner Doug Wright (I Am My Own Wife) also penned the play Quills and the screenplay for its film version. Composer Frankel was musical director for Broadway's Falsettos and Putting It Together and lyricist Michael Korie co-wrote the opera Harvey Milk and lyrics for the Broadway-aimed Lucy Simon musical Zhivago.

Tickets ($86.25-$111.25) are available by visiting www.telecharge.com or calling (212) 239-4200. The Walter Kerr Theatre is at 219 W. 48th Street.

Balcony seats ($36.25) are only available in person at the box office.

For additional information, visit www.greygardensthemusical.com.