A few minutes later, the peace of the place was broken in a different fashion.

There was the sound of a key being hastily fitted into the lock of the outside door.
The dog rose to his feet expectantly.

The door which led into the apartment was thrown open and hastily slammed to.

A man, breathing heavily, stood for a moment upon the threshold, his head stooped a little as though listening.

Then, without a glance, even, at the dog who jumped to greet him, he crossed the room with swift, stealthy footsteps.
Before he could reach the other side, however, the door which faced him was opened.