It's the second in a trilogy of Alfred Hitchcock's spy movies (along with "The 39 Steps" and "Sabotage"). Set during World War I, John Gielgud plays British novelist Edgar Brodie who discovers that a government agency has faked his own death. He is then given orders to travel to Switzerland to kill a German agent.
He goes by the name of Richard Ashenden and travels with secret agent Elsa Carrington (Madeleine Carroll), who poses as his wife. Richard joins a professional killer named "The General" (Peter Lorre) to look for clues, which leads them to suspect the tourist Caypor (Percy Marmont). (A public domain movie)
You can tell that Alfred Hitchcock spent allot of time thinking about his first spy film by the improvements in this one. One thing that stood out for me was the very different role women played in spy stories in the 1930's. Women had just gotten the right to vote 16 years ago through the "woman suffrage" voting rights amendment. Women were only just being allowed to seek higher education. So when you compare the view of women above (which may very well be the Republican view of women today) with the more modern version of women's roles in spy film's you get to see what 95 years of progress on women's rights (as a subset of society) looks like (with better stunts... going down a bunch of stairs was the biggest stunt scene in Alfred Hitchcocks movie but, the actors did the stunts themselves);
Modern Spy Film of which Alfred Hitchcock's movie, above, was a predecessor: