Alistair Urquhart is a Scottish soldier captured by the Japanese in Singapore in 1942 and put to forced labor on the Thailand-Burma Death Railway, where torture and starvation kill men around him daily. The film follows his account through the disasters that come next: a cargo ship carrying him to Japan is torpedoed by an American submarine, and Urquhart is one of the few men to survive, drifting alone in the South China Sea for days before a Japanese whaling vessel picks him up. Sent to another POW camp, this one in Nagasaki, he is close enough to see and feel the second atomic bomb detonate. He tells this story himself, at 91, decades after the British authorities ordered him to stay silent about what he had witnessed. His wife died without ever hearing it. The film stays with his testimony and the historical record around it rather than restaging events, tracking one man's survival through a string of catastrophes that each killed tens of thousands of others.