Shayna fights exhaustion, and props herself up against the door to keep an ear on the outside. Though physically present, her mind is miles away; on her sister and the refugee camp she hoped to visit tomorrow or soon after. The refugee camp that Martin had slipped away to investigate not long after Shayna’s own group had rushed into the trees and fought the walkers.
Besides the howling of wolves earlier, Shayna doesn’t hear a sound as the hours of her watch slip by.
She
doesn’t hear the sounds of someone trodding towards the cabin. She doesn’t hear the sounds of someone circling the cabin in the dead of night. She doesn’t see a grisly and half demented face pressed against the glass, the breath of which fogs up the glass as whoever is without takes the tally of who is within.

She doesn’t hear the dark man outside’s hurried and repeated whispers:
"Give it back! Give it back! Open up! Let us in! Give it back!"
What Shayna’s does hear, a moment too late, is the sound of a shotgun be prepped to fire.
chhk-chhk…
And then the exploding sound of gunshot ripping through the cabin’s door, only a few inches from where Shayna had set her head! A second later - a thunk, and a hiss as something heavy is tossed into the blasted hole.
hissss…
Smoke quickly starts to fill the small cabin as it escapes from the metal canister rolling into the center of the room!