During World War II, John Ford worked as chief of the Field Photographic Branch of the OSS, the intelligence agency that preceded the CIA. When he went on active duty, Ford had already directed 1941’s Sex Hygiene, an Army training film with tips for avoiding the clap and the syph on R&R leave (“I looked at it and threw up,” was the review Ford later gave Peter Bogdanovich). To this, Lt. Commander John Ford added the Oscar-winning documentaries The Battle of Midway and December 7th. Bogdanovich writes that, after the war, Ford’s group began work on a seven- or eight-hour film that was to have been used as evidence at the Nuremberg Trials; in the end, the task fell to Budd Schulberg, also a member of the Field Photographic Branch, whose The Nazi Plan was entered into evidence at Nuremberg.

Some of Ford’s wartime movies were exclusively for OSS consumption, such as 1943’s How to Operate Behind Enemy Lines, a/k/a Undercover, an instructional film about how to be a spy. Like most movies of its kind, it teaches by illustrating dos and don’ts—Ford appears in the only speaking role of his career as the pipe-smoking case officer assigned to the “don’t” agent—and lays heavy emphasis on a single lesson, here the supreme importance of maintaining a believable cover story. Agonizing sequences depict spies blowing their cover through inattention to detail: anything from paying the bar tab with bills no longer in circulation to using “hair grease” they can’t get in Enemytown since hostilities began.
 

John Ford in ‘Undercover’ (via National Archives)
 
Undercover is available on Netflix, but the dialogue sounds like it was recorded with a Kleenex stretched over one end of an empty cookie dough tube, as if all the Allies’ microphones had been melted down for the war effort. The YouTube version embedded below is much easier to follow. If I owned a movie house, I’d program this with the short Don’t Kill Your Friends, a contemporary U.S. Navy training film starring my own grandfather as an inept pilot who offs civilians during aerial gunnery practice.