In this thrilling aviation adventure, young Americans Tom Raymond and Jack Parmly join the French air service during World War I. Eager to fly for France, they complete their training and head to the front lines near Verdun. But danger lurks both in the skies and on the ground. A German spy has stolen plans for Tom's father's new airplane invention, and Tom hopes to recover them. Meanwhile, Jack finds himself drawn to a mysterious girl with an overbearing...