As the officers prepare to enter the North Tower from the concourse, the South Tower begins to collapse onto them, and McLoughlin realizes that their only chance of survival is to take shelter in the elevator shaft. McLoughlin, Jimeno, and Pezzulo are the only survivors, but they are trapped beneath the rubble. Pezzulo tries but fails to free Jimeno, whose lower half is pinned. McLoughlin, who is also pinned, listens helplessly as the North Tower begins to collapse. Pezzulo is fatally injured when a concrete slab crushes his torso, but manages to fire his sidearm once into the air, in an attempt to alert rescuers to their whereabouts just before dying. Jimeno and McLoughlin spend painful, terrifying hours under the rubble telling each other about their lives. Meanwhile, their families try to learn if they are still alive.