He worked in Cinecittà, where he befriended expatriate film producer Paul Maslansky.
[3] Kiefer was the main director of the gothic film Castle of the Living Dead (1964).
Italian prints and posters instead credited "Herbert Wise" as the director of the film.
[2] Kiefer was the director of three more Italian films: Next of Kin (1968), Juliet De Sade (1969), and Defeat of the Mafia (1970).
All his work reportedly was produced in Italy, and Italian directors received the official credit for the films.
[2] The novel was set in the Democratic Republic of the Congo, at the period following the assassination of Patrice Lumumba (1961).
By his own account, Kiefer had visited the Congo, and his experiences there served as a background for the novel.
He lived the rest of his life in Buenos Aires until dying of a heart attack in 1995.