Set months in the past, Howard is talking to forensic archaeologist Matt Jukes about his great-grandfather, Hugh Bellamy, who served in the First World War and went missing in action, never to be seen again. Howard’s tried to track him down for years and recently managed to turn up some old diaries from an officer, Joshua Wise, who reports to have seen Hugh on the day he went MIA – but there are pages missing from his diary that leaves the story incomplete. Howard wants Matt to lead his next archaeological dig in France to look for Hugh’s body and bring back his ancestor who, for years, has had the suspicion of being a deserter hanging over him.

As Howard and Matt read the diary, we see the events of the day of Hugh’s disappearance from Wise’s perspective. After a tense stand-off on the frontline, Hugh assists a man, Zulman Choudry, in transporting an injured Wise and the trio bed down in a barn. They are disturbed by a German patrol but all three manage to survive the night. While the missing pages mean there’s no indication of what then happened to Hugh and Zulman, we then discover they both heroically sacrifice themselves to save Wise.

In the present, Howard is at an airport ready to fly to France when he’s met by Zainab – the great grand-daughter of Zulman Choudry and his closest link to his own grandfather. When they arrive in France, Matt shows Howard and Zainab to the resting places of Hugh and Zulman, hundreds of metres apart in France. He also produces the missing pages from the diary, which reveal the final fates of Hugh and Zulman – exonerating Hugh once and for all from any doubt of his heroism. Once their respective genetic links have been confirmed, a proper burial is hastily arranged, with their two headstones touching as a permanent reminder of their interlocking fates…