The Black Moth by Georgette Heyer

Richard went slowly back to his chair. After a moment he sat down, staring blankly out of the window, his hands loosely clasped on the desk before him. So he remained for a long while, immobile. At last, with the faintest of sighs, he moved and picked up a quill. He dipped it in the ink, and, with his other hand, drew towards him a sheaf of papers. Presently he was writing steadily.

For perhaps twenty minutes the quill travelled to and fro across the pages; then it paused, and Richard looked up towards the door.