Full review sometime in the future. In the meantime...
If you're in the mood for a quiet, sometimes even slow in parts, but intensely dramatic WWII POW film, watch The Captive Heart (1946).
In order to avoid being taken by the Gestapo, who are hunting him after his escape from Dachau, a Czech captain takes the identity of a killed British officer just before he's re-captured and sent to a prison camp. To keep up the charade and throw the Gestapo off his scent he begins to exchange letters with the man's wife back in England, who is unaware of the switch.
The dramatic interest is intensified as we learn that the dead man was callous to his wife before the war and they had fallen out. Gradually, the letters rekindle her love for him, while the captain finds himself falling in love with her as well.
This, along with several other intertwined sub-plots of prisoners and their loved ones back in Britain (seen in short flashbacks), forms the core of the story.
Plotwise, there are no rocket flares. But the way the story unfolds is compelling and there's no finer acting in any film than Michael Redgrave's performance as Captain Hasek. Many of the supporting cast are also superb, though few are well known even to film buffs. This buff ranks it in the top 25 films ever made, possibly, but unquestionably in the top 100.
There are many films which show courage in action. But to show the greater kind of courage required merely to endure the unendurable, day after day with no end in sight, and to never lose one's thirst for life and freedom, is a rare cinematic achievement. The Captive Heart does that with supreme skill.