Plot: Wilfred Owen's nephew travels to the site of the Heidenkopf in northern France, an abandoned German front-line trench which was relentlessly bombed during the war poet's two-day ordeal in January 1917. With the help of trench map expert Peter Chasseaud, historians Paul Reed, Andy Robertshaw and Nigel Jones, plus a team of archaeologists, the dig unearths the remains of three soldiers and the entrance to a dug-out