Captain Norman Craig (Ormer Locklear) returns from the Lafayette Escadrille as a shell-shocked veteran, suffering from amnesia. Seeing him wandering around San Francisco, his girlfriend Virginia Ames (Louise Lovely), with the help of Dr. Wayne Leveridge (Sam De Grasse), devises a plan to help him restore his memory. Her family hires Craig to pursue a pair of supposed Russian thieves after the Ames jewels. The doctor, however, has plans to steal the jewels and wants Virginia for himself. An aerial chase ending with a tailspin and crash brings Craig back to his senses. He is able to thwart the doctor's schemes and finally remembers his girlfriend.