An epic drama set during World War One and told through the eyes of two very ordinary young men who enlist in a war they expect will be over within months. This moving, powerful drama, written by award-winning writer Tony Jordan (Life on Mars, The Nativity, Hustle) and featuring an international cast, spans the years of the war from 1914 to 1918. As the conflict unfolds, so do the boys' incredible stories. Thomas and Michael are two young men for whom the war has little mercy, no matter which side they might be fighting for. Over five chronological years, we follow their lives as they grow up, lose friends and find love amid the horrors of the war. The series forms a key part of BBC One's programming to mark the centenary of World War One.