The film follows Jack Hopkins, an aircraft designer with a passion for traction engines. His boss is eager to sell a new supersonic jet plane that Jack has designed to American millionaire Paul Fisher. The first encounter between Fisher and Jack goes badly, and tensions only heighten after Fisher's daughter Kathy damages Jack's prize traction engine "The Iron Maiden", rendering it impossible to drive solo. Jack is desperate to enter the annual Woburn Abbey steam rally with the machine, but his fireman is injured and unable to participate. When all seems lost the millionaire himself is won over by Jack's plight and joins him in driving the engine; the two soon become firm friends.
as Jack Hopkins
as Kathy Fisher
as Miriam Fisher
as Paul Fisher
as Admiral Sir Digby Trevelyan
as Sir Giles Thompson
as Lord Upshott
as Nellie Trotter
as Humphrey Gore-Brown
as Vicar
as Fred Trotter
as Mrs. Webb
as Harry Markham
as Bill
as Sid Ludge
as Sidney Webb
as Albert - Village Constable
as Charlie
as Thompson's Salesman
as Thompson's Salesman
as Senior Rally Steward
as Rally Commentator (voice)
as Mrs. Webb's Teammate
as 'Wrong' Rolls Royce Owner
as Concierge
as Rally Steward
as Race Starter
as Actor
as Fred's Son
as Himself
as Rally Steward (uncredited)
as Steam Rally Spectator (uncredited)
