It was not until the end of the film that I discovered that this was a real life account by Ernest Gordon of the horrors suffered by the allied POW's building the Burma Railroad.
No film can ever show how terrible it was, despite the attempt to film in sequence with the actors dieting in order to lose weight as time went on. The actors would have had to do three years manual labor in the jungle heat for 18 hours a day on 1,000 (or less) calorie meatless slop, while suffering dysentery, beri beri, pellagra, tropical ulcers, regular beatings and other cruelty, all the time unaware of what was happening at home or how the war was going. They lived under the constant fear of being killed once they were no longer useful. By the time they were liberated the survivors were walking skeletons. Why the filmmakers could not find more skinny extras among the thousands available always puzzles me. When the men were lined up for roll call they could have put the emaciated looking actors at the front, and kept the well built lads at the back, dressed in rags to hide their muscular bodies.
I deducted two stars for the aforemention goof, and for the liberation in August 1945, appearing right after the dedication ceremony for the completion of the railroad in October 1943, at which the men were told they would be moved to other camps. Perhaps it was an editing slip up, but the B-24s arrived to bomb the camps, after which another flight arrived dropping leaflets immediately after.
It is a credit to the filmmakers that this relatively low budget movie conveys this terrible period so well. Although few, if any men, who were prisoners working on the Burma Railroad are still alive, despite the disbelief of several commenters this actually happened and should not be forgotten. This should be a "must see" in school history classes.