In 1917, in the Western front, a group of survivors of the British Company Y reach the most forward German trench in a foggy night. They capture a German soldier that advises that evil is in the trench, forcing the soldiers to kill each other, and asks them to leave the place. Only the private Charlie Shakespeare listens and helps the prisoner, while a supernatural force scares and makes the soldiers insane.
Deathwatch
In the middle of World War I, nine British soldiers caught behind enemy lines seek refuge in a complex network of German trenches. What they soon discover is that they aren't alone - and it isn't a German soldier that's hunting them down.