"If I don't put a stop to this, they'll spoil everything," he said to himself.

He stood in an angle of the house, invisible in the darkness, and measured the distance between himself and the gate. The gate was open. To his right, he saw the steps, on the top of which the people were flinging themselves about; to his left, the building occupied by the portress.

The woman had come out of her lodge and was standing near the people, entreating them:

"Oh, do be quiet, do be quiet! He'll come!"

"Capital!" said Lupin. "The good woman is an accomplice of these as well. By Jingo, what a pluralist!"

He rushed across to her and, taking her by the scruff of the neck, hissed:

"Go and tell them I've got the child... They can come and fetch it at my place, Rue Chateaubriand."

A little way off, in the avenue, stood a taxi which Lupin presumed to be engaged by the gang. Speaking authoritatively, as though he were one of the accomplices, he stepped into the cab and told the man to drive him home.

"Well," he said to the child, "that wasn't much of a shake-up, was it?... What do you say to going to bye-bye on the gentleman's bed?"

As his servant, Achille, was asleep, asleep Lupin made the little chap comfortable and stroked his hair for him. The child seemed numbed. His poor face was as though petrified into a stiff expression made up, at one and the same time, of fear and the wish not to show fear, of the longing to scream and a pitiful effort not to scream.

"Cry, my pet, cry," said Lupin. "It'll do you good to cry."

The child did not cry, but the voice was so gentle and so kind that he relaxed his tense muscles; and, now that his eyes were calmer and his mouth less contorted, Lupin, who was examining him closely, found something that he recognized, an undoubted resemblance.

This again confirmed certain facts which he suspected and which he had for some time been linking in his mind. Indeed, unless he was mistaken, the position was becoming very different and he would soon assume the direction of events. After that...

A ring at the bell followed, at once, by two others, sharp ones.

"Hullo!" said Lupin to the child. "Here's mummy come to fetch you. Don't move."

He ran and opened the door.

A woman entered, wildly:

"My son!" she screamed. "My son! Where is he?"

"In my room," said Lupin.

Without asking more, thus proving that she knew the way, she rushed to the bedroom.

"As I thought," muttered Lupin. "The youngish woman with the gray hair: Daubrecq's friend and enemy."

He walked to the window and looked through the curtains. Two men were striding up and down the opposite pavement: the Growler and the Masher.

"And they're not even hiding themselves," he said to himself. "That's a good sign. They consider that they can't do without me any longer and that they've got to obey the governor. There remains the pretty lady with the gray hair. That will be more difficult. It's you and I now, mummy."

He found the mother and the boy clasped in each other's arms; and the mother, in a great state of alarm, her eyes moist with tears, was saying:

“There remained the third possibility, into which, rare and unlikely as it was, everything seemed to fit. Leprosy is not uncommon in South Africa. By some extraordinary chance this youth might have contracted it. His people would be placed in a very dreadful position, since they would desire to save him from segregation. Great secrecy would be needed to prevent rumours from getting about and subsequent interference by the authorities. A devoted medical man, if sufficiently paid, would easily be found to take charge of the sufferer. There would be no reason why the latter should not be allowed freedom after dark. Bleaching of the skin is a common result of the disease. The case was a strong one — so strong that I determined to act as if it were actually proved. When on arriving here I noticed that Ralph, who carries out the meals, had gloves which are impregnated with disinfectants, my last doubts were removed. A single word showed you, sir, that your secret was discovered, and if I wrote rather than said it, it was to prove to you that my discretion was to be trusted.”

I was finishing this little analysis of the case when the door was opened and the austere figure of the great dermatologist was ushered in. But for once his sphinx-like features had relaxed and there was a warm humanity in his eyes. He strode up to Colonel Emsworth and shook him by the hand.

“It is often my lot to bring ill-tidings and seldom good,” said he. “This occasion is the more welcome. It is not leprosy.”

“What?”

“A well-marked case of pseudo-leprosy or ichthyosis, a scalelike affection of the skin, unsightly, obstinate, but possibly curable, and certainly noninfective. Yes, Mr. Holmes, the coincidence is a remarkable one. But is it coincidence? Are there not subtle forces at work of which we know little? Are we assured that the apprehension from which this young man has no doubt suffered terribly since his exposure to its contagion may not produce a physical effect which simulates that which it fears? At any rate, I pledge my professional reputation — But the lady has fainted! I think that Mr. Kent had better be with her until she recovers from this joyous shock.”

It was pleasant to Dr. Watson to find himself once more in the untidy room of the first floor in Baker Street which had been the starting-point of so many remarkable adventures. He looked round him at the scientific charts upon the wall, the acid-charred bench of chemicals, the violin-case leaning in the corner, the coal-scuttle, which contained of old the pipes and tobacco. Finally, his eyes came round to the fresh and smiling face of Billy, the young but very wise and tactful page, who had helped a little to fill up the gap of loneliness and isolation which surrounded the saturnine figure of the great detective.

“It all seems very unchanged, Billy. You don’t change, either. I hope the same can be said of him?”

Billy glanced with some solicitude at the closed door of the bedroom.