On the day of Bruno and Shmuel’s scheduled “great adventure,” it rains heavily in the morning, and Bruno worries that he will not be able to see his friend before leaving for Berlin. Fortunately, the weather improves in the afternoon, and Bruno is able to make his way down the fence to their regular meeting place. When he arrives, Bruno finds Shmuel waiting for him with an extra pair of striped pajamas “exactly like the one he [is] wearing.”

Bruno tells Shmuel to turn his back and strips off his own clothes and dons the striped pajamas. He notices that they do “not smell very nice.” When Bruno is ready, he tells Shmuel that he can turn around now. Shmuel finds it “quite extraordinary” how much alike they look; it is “almost . . . as if they [are] exactly the same.” Bruno comments that this experience reminds him of the plays Grandmother used to put on with him and Gretel. Grandmother always had the right costume for him to wear in any given situation and had told him,

You wear the right outfit and you feel like the person you’re pretending to be.

Shmuel lifts the bottom wire of the fence and Bruno squeezes underneath, getting muddy in the process. When the two boys are on the same side at last, each has an urge to give the other a hug, but neither does. Instead, they walk toward the camp, and Bruno is astonished to discover that it is nothing like what he had thought it would be. Bruno had imagined that the huts would be “full of happy families” and that the children would all be playing schoolyard games together on the grounds. As it turns out, all he sees are crowds of people in striped pajamas sitting on the ground “looking horribly sad” and soldiers in their uniforms laughing or shouting at them.

Stunned, Bruno says that he does not like it here on the other side of the fence and thinks he should go back home, but Shmuel reminds him that he has promised to help find his father. Not wanting to break his word, Bruno stays. The two boys search for clues to Shmuel’s father’s whereabouts for an hour and a half, but they find nothing.

When the skies begin to cloud over again, Bruno tells Shmuel that he is sorry their efforts have been fruitless, and Shmuel, who had not really expected to achieve success anyway, nods sadly. As the two boys head back to the fence, there is a loud whistle and soldiers surround the area in which they are walking. Bruno and Shmuel are pushed to the center of a mob of people marching under the command of the soldiers. Rain begins to pour down, but still the people are forced to march until finally they are pushed into a long room, which is “surprisingly warm” and seemingly airtight. Bruno thinks that perhaps they are being provided shelter from the rain, but Shmuel looks up at him in terror. Bruno tries to console his friend, taking his hand and telling him that he is his “best friend for life.”

At that moment, the doors to the room slam shut with a “loud metallic” ring, and Bruno cannot make sense of what is happening. The people gasp, the room goes dark, and chaos of the greatest extent ensues; Bruno holds tight to Shmuel’s hand and does not let go.