Digging up Russia's missing army
10 January 2014 Last updated at 14:09 GMT
Almost 30 million Russians lost their lives in World War Two - more than any other nation.
The battlefields of the old Soviet Union were littered with the bodies of soldiers who died trying to defend their land from the German invasion.
Seventy years on, a vast number of corpses still lie where they fell. But now a new generation of Russians is searching for the millions of soldiers still considered missing in action to give them a proper burial.
The documentary Burying the Past, produced and directed by Dean Arnett and produced by Olga Ivshina, was broadcast on BBC World TV on Saturday 4 January and Sunday 5 January.
Find out more:
Listen to Lucy Ash's report on the Russians Digging up the dead on the BBC iPlayer.