An international air race is threatened by sabotage.

In 1910, Lord Rawnsley, a wealthy and influential newspaper publisher, sets out to prove that Britannia rules the air as well as the sea by sponsoring the first International Air Race from London to Paris. Although he invites flyers from all over the world to compete for the prize of £10,000, Lord Rawnsley clearly expects the winner to be Richard Mays, his daughter Patricia's intended bridegroom and a young Royal Navy lieutenant. Among the other entrants who converge at Brookley Airdrome with their fragile flying machines are Orvil Newton, an American barnstormer who almost immediately begins competing with Mays for Patricia's affections; Count Emilio Ponticelli, a fearless Italian who brings along his large family; Colonel Manfred von Holstein, a German cavalry officer intent upon bringing glory to the fatherland; Pierre Dubois, an amorous Frenchman bedeviled by six beautiful look-alike girls; Yamamoto, an "inscrutable" Japanese; and Sir Percy Ware-Armitage, a villainous Englishman who proves to be remarkably adept at sabotaging his rivals' aircraft. Once the race across the English Channel begins, mishaps occur with startling regularity. Inventor Harry Popperwell discovers that his plane only works in reverse, and he vanishes in a backward direction towards Scotland; Sir Percy's skulduggery causes Yamamoto's plane to crash-land upon takeoff; von Holstein plunges headlong into a drainage pond; and Sir Percy himself, after sneaking his plane across the Channel at night, lands on top of a train just as it is heading into a tunnel. Eventually the contest narrows down to three possible winners: Ponticelli, Mays, and Newton. But Ponticelli's plane catches fire (more of Sir Percy's sabotage) and Newton delays to effect a midair rescue, thereby permitting Mays to win the race. Lord Rawnsley's glee quickly turns to dismay when the ethical Mays insists upon sharing his prize with his American rival. Newton, however, has no intention of sharing his prize--the fair Patricia--with his British rival.