The character Howard W. Campbell Jr. is used by Kurt Vonnegut Jr. in the novel Slaughterhouse Five, and makes an appearance in the movie of the same name, although in reference to a part of Campbell's life not included in the film version of Mother Night.
Howard W. Campbell, Jr., an American expatriate playwright, Nazi radio propagandist, and Allied spy, writes his memoirs during his pre-trial confinement in 1961 Haifa and learns that people are what they pretend to be. Written by Erik Gregersen {[email protected]}
Howard W. Campbell Jr., an American living in Germany since childhood, is recruited by the United States to become an informer during the upcoming Second World War. What he does become, is one of the leading anti-semetic news broadcasters of Nazi Germany. After the fall of Hitler's Germany, Campbell's government friends arrange for a quiet life in the United States. His life is quiet until a complex web of spies and neo-Nazis draws him back into the life which he once lead. Eventually captured by the Isralies, Campbell's one defense was: "I was an American Spy.
https://www.imdb.com/title/tt0117093/ https://www.sfbg.us/authors/k/kurt_vonnegut/Novels/Mother_Night.htm