A Click in the Plastic

My dial clicked. It was faint, but distinctly audible against the still air inside my compartment. I tested my right arm, lifting it forward millimeter by millimeter. The rigid clear plastic wrapper held me firmly, but my plastic fingertips managed to make contact with the transparent partition beside me. A dull, rhythmic tap echoed inside the blister tray. My joints responded smoothly. Everything appears to be in prime working order, neatly aligned in place.