THE GERMAN ATTACK ON BOAC FLIGHT 777: On this day in 1943, eight German Junkers Ju 88s shot down a civilian airline flight en route from Lisbon to Whitchurch Airport near Bristol. The plane crashed into the Bay of Biscay, killing all 17 on board.

Portugal was a neutral state, and the attack was considered unusually aggressive. Why would the Germans want to violate Portugal’s neutrality?

One theory is that they mistakenly believed Winston Churchill was aboard. Churchill had been in Algiers, so it wasn’t crazy to think he might return via Lisbon, and a man who looked somewhat like Churchill was among the passengers. Churchill himself seems to have accepted this theory.

Another theory is that the Germans correctly believed that Leslie Howard was aboard. Yes, that Leslie Howard—the actor. Howard (born Leslie Howard Steiner) sometimes played seemingly ineffectual men who were either really ineffectual (Ashley Wilkes in Gone with the Wind) or really heroes (the title character in The Scarlet Pimpernel or the Nazi-fighting archeologist in “Pimpernel” Smith). During the war, Howard had devoted himself to making anti-Nazi feature films and documentaries. The story goes that he made fun of Goebbels in one of those films and that Goebbels considered him an exceptionally effective propagandist. He therefore wanted him dead. Another version of the story argues that Howard was on a top-secret mission that involved persuading Franco to stay out of the war. There is enough to “Howard theory” to put it in the “not crazy” category too.

Other passengers included Wilfrid Israel (department store scion of Kindertransport fame), oil businessman Tyrrel Shervington, and engineer Ivan Sharp. A case can be made for why the Germans would have liked to see any of them dead.

Is it all just rubbish? Was the attack on BOAC Flight 777 just a mistake?  An “error in judgment” (as the lead German pilot later put it)? Maybe. But the mystery continues to fascinate many.