I did have a lengthy conversation with an ex River Kwai survivor many years ago now, as we were talking about the film with Alec Guiness.
He was Royal Army Service Corps when he was captured in the roundup what was the fiasco of the Fall of Singapore. Most were sent to the bridge from there and the Railway which had to be cut out of solid rock by hand.
He was a proud but resentful man, he never knowingly bought anything Japaneseand hated them with every breath in his body. He survived but he said an interesting thing. Those men from units that were at the peak of their fitness when caught invariably died first, through lack of enough food and were often diseased first after mosquito bites and struck down with Malaria.
He told me tales of savagery by the guards for pure fun, when someone went for a drink of water and had too much, they stuffed a hosepipe down their throats into their stomachs and then danced on their swollen bellies. He found it very hard to continue without getting choaked up, talking about men and good friends he had lost as if they were still beside him.
So cruel an existence and very hard to imagine.