Fisher was born in Konstanz and received his doctorate from Heidelberg University in 1936 with a thesis on the organization of labour in the German civil service.

According to an account by Fischer published after the war, from 1942 to 1944 he and Heydrich participated in an underground operation that helped Jews escape from Berlin to Sweden via Copenhagen by providing them with forged identification and travel documents.

According to the obituary of Fischer by Eckhard Becker in the Rhein-Neckar-Zeitung, a Gauleiter and former Nazi student leader at Heidelberg university convinced Heinrich Himmler to commute his friend's death sentence to imprisonment.

He also began writing screenplays which included those for Liebe 47, Wer fuhr den grauen Ford?, and Bernhard Wicki's debut film Warum sind sie gegen uns? [de].

Later in his career he made television documentaries on the theatre directors Fritz Kortner and Erwin Piscator and served as a consultant on film funding to the German Interior Ministry.