Variety reports that Collins will play Gilbert Marshall and Roberts will be Oscar Wolfe.

The duo join the previously announced Tony winner John Glover as Herbert Dean, Tony Award winner and Oscar nominee Rosemary Harris as Fanny Cavendish, Tony Award nominee and Drama Desk Award winner Jan Maxwell as Julie Cavendish and Tony Award nominee and Drama Desk Award nominee Reg Rogers as Tony Cavendish. Doug Hughes directs.

Opening night on Broadway will be Oct. 8.

"It's half past one in the fabulously cluttered Cavendish duplex in the East Fifties, and anyone who's anyone is still asleep. So begins The Royal Family, the classic comedy of theatrical manners. . . .," according to press notes. "This devilishly funny play follows the Cavendishes, the famous family of stage stars, as they go about the drama of the day: choosing scripts, dashing off to a performance, and stealing kisses with handsome beaus. But what's this business about the younger Miss Cavendish wanting to quit the stage for domestic bliss? Never, darling!"

Tony Roberts received Tony Award nominations for his performances in Play It Again Sam and How Now, Dow Jones. His other theatrical credits include Xanadu, Victor/Victoria, Barefoot in the Park, Don't Drink the Water, Sugar, Absurd Person Singular, Arsenic and Old Lace, They're Playing Our Song, Jerome Robbins' Broadway and The Sisters Rosensweig. He won the London’s Critics Poll Award for his performance in the West End mounting of Promises, Promises, and his many screen credits include "Annie Hall," "Play It Again, Sam" and "Serpico." Stephen Collins has been seen on Broadway in Spamalot; Moonchildren; No Sex Please, We're British; The Ritz; Censored Scenes From King Kong; and The Loves of Anatol.

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