It had just gone nine o'clock on that same eventful evening when the limousine slowed down before Scotland Yard, and the car was handed over to its natural owners. Superintendent Narkom, Cleek learned to his extreme relief, was engaged on a special case involving his working at the Yard to a late hour. In the fraction of a second Cleek was ascending the stone staircase and traversing the corridor, at the end of which lay the private room of his friend and ally. He still felt that all was not as it should be at Cheyne Court, and even though he was unable to do anything at the moment, yet he felt he must pour the story of his adventure into the trained and sympathetic ears of the man with whom he had worked so long and so faithfully. It could not have been more than a minute, but the time seemed endless till he at length, after a preliminary tap, threw open the door of the room and saw the figure of Mr. Narkom ensconced in his arm-chair, his brows knitted, and his hands clenched over a sheet of paper lying on the desk before him. He looked up irritably at the evidently unwelcome intrusion. "Now, what the----" he began. Then as he caught sight of the intruder, he leaped from his seat and fairly hurled himself on Cleek. "Cleek!" he shouted. "Cleek, the very man I was praying for! Come along in and lock the door behind you so we can't be disturbed." Cleek obeyed, smiling a little. He was always willing and eager to give his help to the Yard, and the very fact that Mr. Maverick Narkom so plainly depended on him lent still further zest to his willingness. "Hello," he said lightly, "you look fairly dazed, Mr. Narkom. What's in the wind? It's a case, of course. And a jewel case at that," he added. "Cinnamon! Cleek," stuttered the Superintendent, falling limply into his lately vacated chair. "How the dickens did you know, or are you----" "In league with the Evil One himself, eh?" finished Cleek, the queer, one-sided smile travelling over his face. "No, it's quite simple, my dear fellow. At your side you have a book, 'Famous Stones and Their History.' In front of you is a lapidary's glass. Clearly you have been examining stones of some kind, real or artificial, see?" "Yes, I do see," muttered Mr. Narkom. "And you're right Cleek, devilish right. It _is_ a jewel theft. As a matter of fact, it's a series of thefts, all by the same gang, and Heaven alone knows how or from where they operate." "Oho!" said Cleek, with a strong rising inflection. "A gang, eh? Now I wonder if I know. There's the French gang, headed by our old friend Margot; the Viennese gang, by Mr. Von Henri, and the Lambeth Walk gang that have called themselves the Pentacle Club----"