The third act begins on the following day, just before sunset. Stanhope is anxiously pacing the dugout and checking his watch. The colonel enters and they discuss how the Germans are expecting the raid, and how they should alter their plans to make a secret raid further up the line. But the colonel says the generals said the current plan has to stay. The report has to be back at headquarters by seven; if they wait until dark it’ll be too late. Stanhope says that they can’t have it later because of dinner. Stanhope says that with only one hole blown in the defenses, the Germans must have a dozen machine guns trained on the entrance, waiting for the raid. The colonel says he can’t disobey orders, and it’s no use arguing about it now.
Osborne and Raleigh enter. The colonel encourages them to grab the first German they see, and say it may mean the difference in winning the whole war. If they’re successful, he’ll recommend them for the M.C. (Military Cross). On his way out, he reminds them to not carry any papers or personal effects. Osborne asks Stanhope to take his wedding ring and watch to send to his wife should anything happen.
Alone in the dugout, Raleigh and Osborne drink coffee and smoke while discussing the plan: Osborne predicts it will be over in three minutes. Osborne suggests they forget all about the raid for the six minutes they have to wait. He tries to talk about favorite breakfast drinks but Raleigh keeps asking questions about the Germans. After passing the time reminiscing about forest walks, they go up the steps.
Through the hole in the dugout, the audience hears the crush of smoke bombs, the rattle of machine-gun fire, and then the sound of bombshells. Stanhope and the colonel enter the dugout. Stanhope looks deathly pale. Rather than stay for the questioning, he goes up again, saying he’d rather talk to the men.
The sergeant-major carries down a bare-headed German soldier crying bitterly. In poor German, the colonel questions the young soldier, who pleads for mercy. The sergeant-major finds the boy’s pocketbook and his playbook and gives them to the colonel. The sergeant-major takes the German away.
Stanhope enters and the colonel is pleased to tell Stanhope that from the playbook he can see the boy’s regiment came into the line last night; the brigadier will be pleased. The colonel asks if the raiding party is safely back and Stanhope says only four men and Raleigh returned. Stanhope says Osborne died by hand-grenade while he was waiting for Raleigh; the six men likely died by machine-gun bullets. The colonel struggles for something to say as Stanhope stares at him.
Raleigh enters the dugout with bleeding hands. The Colonel commends him for a job well done but Raleigh is too shocked to respond. The colonel gets him to sit on the edge of Osborne’s bed. He leaves. Stanhope stares at Osborne’s watch and ring on the table. He leaves, but stops on the steps and asks in a dead voice if Raleigh has to sit on Osborne’s bed. The curtain falls.
On the day of the raid, Stanhope is frustrated at the colonel and the generals after they only managed to blow a hole in the German defenses in one spot. This means the Germans will be waiting with guns trained on the single entrance.
In addition, the generals have asked the raid to happen during the more dangerous daylight hours—simply because they don’t want a discussion of the raid’s findings to interfere with their dinner. But the rigid hierarchy of the military means that Stanhope must follow the orders of men who are out-of-touch and unconcerned with the lives of the soldiers; Stanhope must send those soldiers to almost-certain death.
The colonel’s exchange with Raleigh and Osborne touches on the theme of heroism: in contrast to the reluctant manner in which he and Stanhope discuss the raid, to Raleigh and Osborne he feigns pride and entices the men by suggesting that they could receive the Military Cross honor for a successful mission. In contrast to his confident announcement, the colonel then reminds the men to not carry anything the Germans could use against the British should they be captured.
After the raid, Stanhope’s pale figure foreshadows that something terrible has happened. The tension is not released until Stanhope reveals to the pleased colonel that Osborne died during the raid. The measly documents the colonel took from the captured German are nothing in comparison to the seven men who died during the mission, which Stanhope had known would result in casualties.
In an ironic reversal of the audience’s expectations, the experienced Osborne died while the inexperienced Raleigh survived. But Raleigh returns to the dugout clearly traumatized. Though moments earlier he went into the raid fresh-faced and excited by the prospect of being a hero, he returns horrified by the gruesome reality of war. However, the final moment of the scene suggests that Stanhope is not sympathetic to Raleigh: rather than console him, Stanhope asks angrily that Raleigh not sit on Osborne’s bed. The tense exchange implies that Stanhope may blame Raleigh for Osborne’s death, as Osborne was waiting for Raleigh to return when the grenade killed him.