Against the Wind (1948)
Bloody good war film about saboteurs dropped into and infiltrating Nazi held Belgium to wreak havoc with help from local resistance fighters.
Thought I'd seen it before, but no, something very similar that was set in France and just as good as that one, with quislings and double agents.
So, a number one Belgian agent destroys a Nazi records office that holds thousands of names, but after completing the mission, he is rumbled and arrested - the job is then on to rescue him.
Head of the British agents is James Robertson Justice (superb), who oversees the band of spies/saboteurs played by Jack Warner (one of my faves), Gordon Jackson, John Slater and Simone Signoret (gorgeous) were faces I knew, and there were others in the group. The mission was difficult as it was, but one of them is also a double agent.
Gripping to the end.