Lisa D'Amour's drama premieres in Chicago before opening on Broadway.
The former member of The Pussycat Dolls takes on Andrew Lloyd Webber.
The famed rock star joins the show for a limited engagement.
The new drama stars Justin Kirk and Usman Ally.
The new musical plays in France before moving to Broadway.
Stephen Sondheim and James Lapine's Tony-winning musical is now a major motion picture.
The show is hosted by Modern Family's Jesse Tyler Ferguson.
Jon Hamm and Edward Norton were also among the guests who took in Bernard Pomerance's drama at the Booth Theatre.
The concert kicked off Brown's tenure as an artist-in-residence at the swanky venue.
The Ahrens and Flaherty musical at York Theatre Company also stars Leslie Kritzer and Rose Hemingway.