As a tail gunner on an Avro Lancaster bomber, Sergeant Lex Duffield was used to danger in the sky.

However, more even danger soon appeared in the unlikely form of a fellow Lanc rear gunner — the reckless and short-tempered Sergeant Tommy Deakin — and inevitably they clashed.

Fate soon intervened and they faced a threat neither could possibly have imagined — and they would just have to work together to survive.