Then, on its arrival in America, the new picture was easily cleaned off, the back removed, and lo! it was an old master once more ready for purchase at a high price by American collectors.

Truly, the gloved hand of The Sparrow was a master hand. He had brought well-financed and well-organized theft to a fine art. His “indicators,” both male and female, were everywhere, and cosmopolitan as he was himself, and a wealthy man, he was able to direct—and finance—all sorts of coups, from a barefaced jewel theft to the forgery of American banknotes.

And yet, so strange and mysterious a personality was he that not twenty persons in the whole criminal world had ever met him in the flesh. The tall, good-looking man whom Dorise knew as the White Cavalier was one of four other men who posed in his stead when occasion arose.

Scotland Yard, the Surete in Paris, the Pubblica Sicurezza in Rome, and the Detective Department of the New York police knew, quite naturally, of the existence of the elusive Sparrow, but none of them had been able to trace him.

Why? Because he was only the brains of the great, widespread criminal organization. He remained in smug respectability, while others beneath his hand carried out his orders—they were the servants, well-paid too, and he was the master.

No more widespread nor more wonderful criminal combine had ever been organized than that headed by The Sparrow, the little old man whom Londoners believed to be Cockney, yet Italians believed to be pure-bred Tuscan, while in Paris he was a true Parisian who could speak the argot of the Montmartre without a trace of English accent.

As a politician, as a City man, as a professional man, The Sparrow, whose real name was as obscure as his personality, would have made his mark. If a lawyer, he would have secured the honour of a knighthood—or of a baronetcy, and more than probable he would have entered Parliament.

The Sparrow was a philosopher, and a thorough-going Englishman to boot. Though none knew it, he was able by his unique knowledge of the underworld of Europe to give information—as he did anonymously to the War Office—of certain trusted persons who were, at the moment of the outbreak of war, betraying Britain’s secrets.

The Department of Military Operations was, by means of the anonymous information, able to quash a gigantic German plot against us; but they had been unable to discover either the true source of their information or the identity of their informant.

“I’d better be off. It’s late!” said Mr. Howell, after they had been in close conversation for nearly half an hour.