"The MacIver brothers (Michael Redgrave, Griffith Jones) build the first ship to cross the Atlantic by steam power alone."
Michael Redgrave
as Charles MacIver
Valerie Hobson
as Mary Ann Morison
Griffith Jones
as David MacIver
Hartley Power
as Samuel 'Sam' Cunard
Margaretta Scott
as Susan Donaldson
Bessie Love
as Begonia Baggot
Milton Rosmer
as George Burns
Frederick Leister
as James Morison
Henry Oscar
as Josiah Eagles
Edmund Willard
as Robert Napier
Charles Victor
as Tim Grogan
Frank Tickle
as Mr. Donaldson
Leslie Bradley
as Horatio Stubbs
Felix Aylmer
as Bank President
Joss Ambler
as Dr. Lardner
Ian McLean
as Capt. Woodruff
Joe Cunningham
as Capt. Slade
John Salew
as Henry
Hélène Burls
as Minor Role (uncredited)
Arthur Goullet
as Minor role (uncredited)
James Harcourt
Roddy Hughes
Harry Lane
Jean Lester
Aubrey Mallalieu
Princess Margaret
as Princess Margaret (archive footage)
Elizabeth II of the United Kingdom
as Princess Elizabeth (archive footage)
Queen Elizabeth the Queen Mother
as The Queen Mother (archive footage)
Ian Wilson
as Extra (uncredited)
Edward Dryhurst
Screenplay
Emeric Pressburger
Walter Forde
Director
Gordon Wellesley
Derek MacIver
Story
Norman G. Arnold
Art Direction
Henry Harris
Special Effects
Jack Beaver
Music Director
Basil Emmott
Director of Photography
Wynne MacIver
Ernest A. Royls
Sound
Douglas Woolsey
Terence Fisher
Editor