From 1933 he played at the Nuremberg Intimate Theater, from 1934 he belonged to the ensemble of the Berlin "Cabaret of Comedians" on Kurfürstendamm and acted in many films, e.g. with Gustaf Gründgens, Zarah Leander, Theo Lingen, Margit Symo (mother of Tatort actress Eva Mattes ) or Anny Ondra.

Dorsay himself did not rejoin the party despite the persuasion of Reich Chamber of Culture official Hans Hinkel.

In March 1943, while on leave from home, he caught the eye of a Gestapo informer while telling a political joke in the restaurant of the Deutsches Theater.

On 31 March a letter from Osterode to his friend Eddy Haase was intercepted in Berlin, in which he wrote:"When will this idiocy finally end?"

He was arrested and sentenced to death on 8 October 1943 for undermining military force and sent to Plötzensee where he was executed.

The death sentence was intended to deter other artists; his name was systematically removed from the opening credits of the films in which he had acted.