Read it through once

Its disappearance, however, was but momentary. With a rending, tearing sound, one of the broad, white stones turned over upon its side and left a square, gaping hole, through which streamed the light of a lantern. Over the edge there peeped a clean-cut, boyish face, which looked keenly about it, and then, with a hand on either side of the aperture, drew itself shoulder-high and waist-high, until one knee rested upon the edge. In another instant he stood at the side of the hole and was hauling after him a companion, lithe and small like himself, with a pale face and a shock of very red hair.