“And you hung the key there on the nail above the chart desk?”
“Yes.”
We both swung hastily around. At the other end of the shadowy corridor gleamed the green-shaded light over the desk. With one accord we started toward it.
The key was not on the nail above the desk!
But even as our frightened gaze took in that amazing fact my eyes fell on the glass top of the desk. There on its shining surface lay the key. We stared at it for some time before our eyes met. Then I picked up the key, my fingers seeming to shrink from the cold, clammy metal, returned to the south door, locked it securely and put the key in my pocket.
And as I did so, a thought struck me. The person who had got into the wing by means of the south door must also have got out again. He couldn’t have gone through the corridor and south door for Maida was, by that time, in the hall.
The light was still glowing in Room 18, and I crossed the room, not without a queer feeling in the region of my knees, as if they would give way with me, without notice. Sure enough, the window was unlocked; it was even open a fraction of an inch at the bottom, though the screen, which has a spring snap, was closed.
I pushed the window the rest of the way down, locked it, not without an unpleasant impression that something was out in that gleaming darkness back of the window pane watching my every move, turned off the light, and closed the door again. Maida was standing in the corridor and we walked slowly toward the more cheerful region of the chart desk and diet kitchen.
“I suppose,” she mused at length, “that someone could have taken the key from the nail and returned it when we were in Room 18.”
“But who? It would have to be someone in St. Ann’s. And that is unthinkable.”