Either they were coming up the steps already, or had gone to reach the parapet some other way.

It did not occur to me, or for that matter to any of us in the excitement of the minute, that they might be holding a consultation below, or might even have abandoned the idea of following, although I think now that must be the explanation, for what we did took more time than it takes to set it down.
Ben Hamza made one end of the rope fast around Abdul Ali's feet.
He would not listen to argument.

He said he knew his business, and certainly the knot was workmanlike.

Then he called over the parapet (an Arab never whistles) and a voice answered from the southern side of the moat, where some fallen stones cast a shadow.

Then the three of them lifted Abdul Ali over, and lowered him head-first.
It was a slow business, for otherwise he would have been stunned against the first projection.