The Hour Before the Dawn is an interesting little World War II film. Based on a novel by W. Somerset Maugham, the 1944 film stars Franchot Tone and Veronica Lake (without her signature peek-a-boo hairstyle). At just 75 minutes long, the film is short, but still packs a punch. Although I feel the plot is not completely developed, the storyline and characterizations that exist are meaningful.
Jim falls in love with and marries Dora Bruckmann, an Austrian refugee who works for his family. Although he only sees the good in her, it is evident that Dora (played nicely by Veronica Lake) is hiding her true identity. We soon discover that Dora is a Nazi agent, using the idealist Jim as she plots to help Hitler invade the English countryside.
link to the video I found on Youtube. It's not great quality (as you can see in my screencaps), but it works!