“Exactly. I see it all quite plainly,” Dudley answered. “I trust you will experience little difficulty in discovering the man for whom you are searching. I need not say how extremely anxious I shall be to see the strange matter elucidated, so that the mystery may once and for all be cleared up.”

“I am working unceasingly towards that end, Mr Chisholm,” answered Cator with a meaning look in his quick grey eyes, as he drained his glass and rose. “And now I have only to apologise for intruding upon you at such an unearthly hour.”

“Apology is quite unnecessary,” Dudley assured him. “It appears that the matter personally concerns me in some extraordinary manner.”

“Yes,” replied the chief of the secret service. “So it seems. But we shall know more later, I hope. My staff are on the alert everywhere. As every confidential agent that England possesses on the Continent is at work endeavouring to unravel the mystery of Mayne Lennox, I am very hopeful of success. And success will allow England to make a counter-stroke that will paralyse our enemies and ‘frustrate their knavish tricks,’ to quote a suppressed line from the National Anthem.”

“I wish you every luck,” said the Under-Secretary, shaking the other’s thin and chilly hand. “As I can’t persuade you to remain the night, I hope you’ll have a comfortable journey up to town.”

“Not very comfortable, I anticipate,” the captain laughed, surveying himself. “I’m in an awful state—aren’t I? It was so late when I got to Shrewsbury that I couldn’t get a conveyance anywhere, so in desperation I tramped over here.”

“Well, Barton shall drive you back; you’ll have plenty of time for your train. When do you return to the Continent?”

“Perhaps at once—by the eleven from Charing Cross. It all depends upon a telegram which I shall receive on arrival in town. My future movements are extremely uncertain. They always are. From one hour to another I never know in which direction I shall be hurrying.”

Chisholm had heard of this man’s rapidity of movement. Indeed, it was whispered in his own circle in the Foreign Office that Archie Cator would often retire to his bachelor rooms in Rome, and cause his man, Jewell, to give out that his master was indisposed, and confined to his bed; though, as a matter of fact, the chief of the Confidential Intelligence Department would be flying across to Berlin, Vienna, or Petersburg on a swift and secret mission. He lived two lives so completely that his ingenuity surpassed comprehension. In Rome, only his servant and the Ambassador knew the truth. Even at that moment the diplomatic circle in the Eternal City believed their popular member, Captain Archie Cator of the British Embassy, to be suffering from one of his acute and periodical attacks of the rheumatic gout which so often prostrated him.

Dudley himself conducted his distinguished visitor down several stone corridors into the servants’ quarters. In the courtyard outside stood Barton with the dog-cart, the light of the lamps showing that the snow was still thawing into thick slush.