Mapping the Threshold

I advanced along the sneaker's rubber rim toward the gap beneath the front door. The airstream was steady. A faint drift of fine gravel had gathered along the metal weatherstrip, forming an uneven ridge. I unclipped my blaster and used the barrel tip to rake the particles aside, clearing a stable foothold. With both boots secured against the brushed aluminum strip, I peered through the narrow millimeter slit. Beyond lay a sunlit concrete landing and a patch of green grass. The outdoor sector is clear and accessible.