It all starts when Tintin tries to help a plane in trouble. The pilots shoot at him and run away. Tintin is hospitalized but starts his investigations as soon as he feels a little better. One day, Pushchov, who is the leader of a gang of forgerers and the person behind the plane incident, recognizes Tintin at a train station. Be boards the same train to try to get Tintin arrested for assault and burglary. After a few times of Thompson twins loosing Tintin and Tintin escaping them, Tintin finds a crashed plane on his way to Eastdown. He looks around for clues and finds a flying jacket with a few pieces of papers in its pocket, from which he figures out his next step. His investigation leads him to Dr. Müller's house where he gets caught in a man-trap. Müller tries to kill him which results in a fight, in the course of which the house catches fire. Müller escapes and Tintin is rescued by the firemen.