"It's a Boy" stars Horton as Dudley Leake, who is betrothed to Mary Bogle (the very pretty Wendy Barrie). Shortly before the wedding, Dudley blurts a confession to his friend and best man, Jim Skippett: 20 years ago, Dudley had a brief affair with a certain Miss Piper, but he's never heard from her since then. Next day, who should suddenly appear? A youth about 19 or 20 years old, claiming to be named Joe Piper. Is he Horton's son, or is Skippett playing a practical joke?
Cast

Leslie Henson
James Skippett

Albert Burdon
Joe Piper

Edward Everett Horton
Dudley Leake

Heather Thatcher
Anita Gunn

Alfred Drayton
Eustace Bogle

Robertson Hare
Allister

Wendy Barrie
Mary Bogle

Helen Haye
Mrs. Bogle

Joyce Kirby
Lillian

J.H. Roberts
Registrar
Clifford Buckton
Inspector Burns

Finlay Currie
Publisher
Gladys Hamer
Bride at Registrar's Office
Grethe Hansen
Unknown
Roddy Hughes
George
Crew

Tim Whelan
Director

John Paddy Carstairs
Scenario Writer
Leslie Howard Gordon
Scenario Writer
Franz Arnold
Screenplay
Ernst Bach
Screenplay
Austin Melford
Screenplay
Harold Young
Editor
Mutz Greenbaum
Director of Photography

Michael Balcon
Producer
Ian Dalrymple
Production Assistant
Gordon Conway
Costume Design
Slim Hand
Sound Recordist
Louis Levy
Music Director
Frank Cadman
Unit Production Manager
Alex Vetchinsky
Art Direction