In Biggles Follows On, Stresser was an operative in von Stalhein's espionage ring whose main mission was to encourage military personnel from the West to defect so that they can be used for propaganda purposes. Stresser was employed as a runner. His main job was to act as a minder, receiving defectors and escorting them to behind the Iron Curtain.
Biggles first met Stresser when they were at Paris Le Bourget airport. Stresser was there waiting for Guardsman Ross to escort him to Prague. Biggles was wearing the special identification tie of the ring: black with red spots so Stresser rather indiscretely started a conversationn with him.
Stresser told Biggles he was rather dissatisfied with his job. He had heared there was good money in it but he hardly earned enough to live. Nor had there been any advancement---he had served as a "Laufbursche" (errand boy) for years.
Stresser revealed that he would be staying with Ross at the Hotel Schweiz on the Moldaustrasse in Prague.
The day after their arrival in Prague, Stresser passed Guardsman Ross to another minder who took him on to Berlin. Biggles was unable to follow after Ross any further and besides, had run into von Stalhein at the airport, and had to make a hasty escape.
To regain the trail, Biggles decided to take a risk and and return to the hotel to find Stresser. When they met, Biggles offered him a bribe of a thousand marks if he would talk. Stresser, unable to resist the temptation, told Biggles that Ross would be sent to East Berlin first, when he will be staying at the Hotel Prinz Karl on the Zindenplattzer. Thereafter he would be sent to Kratsen, in Manchuria.
Later, Stresser made a full confession to von Stalhein about what had happened between him and Biggles, which sent von Stalhein hurrying to Kratsen to forestall him. One can assume that Stresser, in the light of his confession, was "taken care of" by the Communist authorities.