Wall Tap

My neck twitched first, loosening with a tiny plastic click. I blinked, looking down at the light wood grain under my boots. Leaning back, my shoulder bumped against a towering plain cardboard box. Wait, I can move? I lifted my right hand, turning it slowly to test each joint, then gave the sturdy cardboard wall a quick, firm tap with my knuckles. A hollow thud echoed back, solid and real.