The Case with Nine Solutions by J.J. Connington

In the course of his career, Sir Clinton Driffield had found it important to devote some attention to his outward appearance; but his object in doing so had been different from that of most men, for he aimed at making himself as inconspicuous as possible. To look well-dressed, but not too smart; to seem intelligent without betraying his special acuteness; to be able to meet people without arousing any speculations about himself in their minds; above all, to eliminate the slightest suggestion of officialism from his manner: these had been the objects of no little study on his part. In the days when he had held junior posts, this protective mimicry of the average man had served his purposes excellently, and he still cultivated it even though its main purpose had gone.

Seated at his office desk, with its wire baskets holding packets of neatly-docketed papers, he would have passed as a junior director in some big business firm. Only a certain tiredness about his eyes hinted at the sleepless night he had spent at Heatherfield and Ivy Lodge, and when he began to open his letters, even this symptom seemed to fade out.