David Wilton, John Aynesworth, and Smith are among a group of cadets hoping to become pilots in the Royal Air Force. David, however, has poor height perception and cannot master his landings. Therefore he is sent to navigator's school, but finds it hard to concentrate on his new job due to despondency over losing his chance to be "something important," a pilot. His friends and teachers join in an effort to show David the vast importance of the navigator, something he learns for himself over the target city of Berlin.