A captain, a well-known flying ace, is developing his own device which will make a notable contribution to the prestige of his country's air force. One evening he occasionally meets a girl who strikes him with her mysterious behavior. In fact, he witnesses some completely inexplicable events that disturb him and take away the necessary serenity of mind to attend to his work, from which he feels detached. An explosion in the laboratory brings to the attention of an entire espionage network that was working to prevent the realization of the project.