Johannes Eppler (1914–1999), also known as Hans Eppler, John Eppler, and Hussein Gaafer, was a World War II Abwehr spy, a German who had been raised in Egypt by his Egyptian stepfather. One of Rommel's spies during the North African campaign in World War II, Operation Salaam led by László Almásy spirited Eppler and Hans-Gerd Sandstede into Cairo although they were both arrested soon after arrival in July 1942. Eppler is the subject of MI5 file KV 2/1467.
Eppler is the subject of a book by Leonard Mosley, The Cat and the Mice, and is again referenced in Mosley's The Druid. Eppler and his radio operator Sandstede are plainly the source for the two German spies portrayed by Lee Montague and Michael Caine in the British film of The Cat and the Mice, retitled Foxhole in Cairo (1960).
A more direct reference is in the German film Rommel Calls Cairo (1959) based upon Eppler's book of the same name. In this film, Eppler is portrayed by Adrian Hoven.
Eppler portrayed Rommel in the French film Le Mur de l'Atlantique (1970).
The film and novel The English Patient also reference Operation Salaam and Eppler's activities.
Eppler's history is the same as that of the character Alexander (Achmed) Wolff, the Cairo spy in Ken Follett's "The Key to Rebecca" (1980).