George Hamilton
— Moss Hart
Jason Robards
— George S. Kaufman
Jack Klugman
— Joe Hyman
Sam Levene
— Richard Maxwell
Ruth Ford
— Beatrice Kaufman
Eli Wallach
— Warren Stone
Joseph Leon
— Max Seigel
George Segal
— Lester Sweyd
Sam Groom
— David Starr
Sammy Smith
— Sam H. Harris
Louise Larabee
— Clara Baum
David Doyle
— Oliver Fisher
Jonathan Goldsmith
— Teddy Manson
Bert Convy
— Archie Leach
Drummond Erskine
— Franklyn P. Adams
Kenneth Mars
— Robert E. Sherwood
Roger C. Carmel
— Hotel Clerk (uncredited)
Janet Fox
— Edna Ferber (uncredited)
Sylvie Strause
— Mrs. Hart
Martin Wolfson
— Mr. Hart
Earl Montgomery
— Alexander Woollcott
Arno Selco
— Bernie Hart
Joe Demar
— Heywood Broun
Bill Desmond
— George Jean Nathan
Allen Leaf
— Harry the Waiter
Lulu B. King
— Maid
Jack English
— Elevator operator (uncredited)
Bryce Holman
— Minor Role (uncredited)