This it what I remember about the movie - there are prisoners in a German POW camp for prisoners who have already escaped from a POW camp. In the camp they are building a glider that can carry two people to safety - I think it will glide from the camp into Switzerland. At the end a scientist becomes one of prisoners to escape because he knows something about heavy water. They get the glider off just at the Gestapo goes into the camp to get the scientist.
Does this sound familiar to anyone? Thanks for any help you can give me.
Duluth Public Library