Deathwatch

Charlie Shakespeare initially refuses to advance and is coaxed along by Sgt. Tate as the unit charges a German trench. Thick fog and the artillery barrage cause chaos, and many soldiers fall to machine-gun fire. The British company quickly becomes lost in the battlefield gloom.

They stumble into a maze-like network of trenches and meet three terrified Germans. Thomas shoots and kills one; another flees; the third, Friedrich, surrenders. Convinced they have broken through the lines, the unit decides to secure the trenches.

As they move deeper, they find rot-filled bodies, barbed wire, and corpses with broken equipment; compasses and watches have stopped working. They detonate charges to close off passages, and an unseen demon-like growl reverberates, with blood pouring from the mud. The eerie discoveries hint that something more than soldiers haunts these tunnels.

Jack Hawkstone is ambushed by the second German hiding in the mud. He and Barry fight the assailant, but Thomas executes the prisoner with a pistol and even scars him, despite Tate’s objections. The acts reveal the unit's moral collapse under pressure.

Attempts to contact command via radio reveal that White Company was believed obliterated during the assault, and communications fall silent soon after. The isolation deepens as the men face the trench's horrors without relief. The fear of being surrounded by enemies seems to grow.

Cpl. Doc Fairweather tends the wounded while Willie isolates himself, unsettled by strange sounds. Barry discovers three German corpses bound in barbed wire; one suddenly animates and attacks him. Charlie and Tate arrive to find Barry's corpse lashed to the wall, a chilling sign that the enemy may be closer than expected.

The men rough-handle Friedrich to learn what is happening; he explains the other Germans turned on each other and warns that there is 'evil' in the trenches. Charlie understands Friedrich through his French, and they realize survival depends on deciphering the trench's mystery. The tension among the soldiers continues to escalate.

The next morning, they pile up German dead and clear dugouts with grenades. Phantom artillery and the clamor of approaching infantry unsettle Jennings, who cracks and accidentally shoots Jack. Morale continues to deteriorate as Willie contemplates desertion.

That night, Willie is chased by a red mist and hears voices, finding himself drenched in blood. He flees into no man's land but is shot by Anthony Bradford; Doc attempts a rescue, but Willie crawls and is pulled under by a tunneling force, dying in the mud.

Haunted by possession, Anthony asks Charlie to shoot him so he won't kill anyone else; Charlie refuses and Anthony runs off, leaving the fate of the trenches in limbo.

Friedrich is crucified alive by Thomas on a wooden beam in no man's land, a brutal act that mirrors the brutal regime that has taken hold of the unit. Thomas then subdues and stabs the insane Jennings to death; Tate attacks Thomas but is ensnared in barbed wire, and Thomas kills Tate. Finally, living barbed wire rises from the mud, and Charlie is forced to shoot his former comrade.

After Thomas's death, Charlie frees Friedrich and arms him with a rifle. He searches for Doc and finds Colin Chevasse, whose legs have been gnawed by rats; Charlie euthanizes him in tears. He then confronts Anthony, who has Doc bound with barbed wire; both plead for Charlie to kill Anthony, but Charlie refuses and Anthony shoots Doc. Shakespeare finally kills the chaplain.

The soil under the German corpse pile caves in and barbed wire blocks every passage. Charlie is sucked down into a pit and wakes in a cavern filled with corpses, where living versions of his unit sit eating together. He flees back to the trenches, only to be confronted by Friedrich, now healthy again, who points a rifle at him.

Friedrich, now calm, tells Charlie he is free to go and gestures toward a ladder leading to no man's land before fading away. Charlie climbs out into the fog of no man's land, stepping into an uncertain fate beyond.

A later British team reaches the trench and spots Friedrich sitting alone. He surrenders with a chilling, ominous stare, suggesting that this nightmare will begin again for another group of soldiers. The film closes on the same terrors returning to the surface world.