Catering salesman Jim Ferguson (Alex Hyde-White) falls through a time hole to 1917, where he saves the life of dashing Royal Flying Corps pilot James "Biggles" Bigglesworth (Neil Dickson) after his photo recon mission is shot down. Before he can work out what has happened, Jim is zapped back to the 1980s. He teams up with Biggles and Air Commodore Colonel William Raymond (Peter Cushing) to stop a revolutionary sound weapon from falling into German hands.