“Jeekes!” cried Robin, slapping his thigh. “He must have been actually coming away from your place when I met him ...”

“And who,” asked the big man, reflectively contemplating the amber fluid in his glass, “who is Jeekes?”

In reply Robin told him the story of Hartley Parrish’s death, his growing certainty that the millionaire had been murdered, the mysterious letters on slatey-blue paper, and Jeekes’s endeavor to burke the investigations by throwing on Robin the suspicion of having driven Parrish to suicide by threats. He told of his chance meeting with Jeekes in Rotterdam that morning, his adventure at the Villa Bergendal, his finding and rescue of Mary Trevert, and their escape.

Herr Schulz listened attentively and without interruption until Robin had reached the end of his story.

“There’s one thing you haven’t explained,” he said, “and that’s how Miss Trevert came to walk into the hands of these precious ruffians ...”

“There, perhaps, I can help you,” said the doctor from behind one of Herr Schulz’s rank cigars; “I have it from Miss Trevert herself. Some one impersonating you Mr.—er, ahem,—Schulz—telephoned her this morning, after she had left her letter of introduction here, asking her to come out to lunch at your country-house. She suspected nothing and went off in the car they sent for her ...”

“By George!” said the big man thoughtfully; “I suspected some game of this kind when I heard of the attempt to get at that letter of introduction. If I only could have got hold of Marbran this morning ...”

“Marbran!” said Robin thoughtfully. “When I read Dulkinghorn’s letter just now I thought I had heard that name before. Of course—Victor Marbran! That was it! I remember now! He knew Hartley Parrish in the old days. Parrish once said that Marbran would do him an injury if he could. Who is Marbran, sir?”

All unconsciously he paid the tribute of ‘sir’ to Herr Schulz’s undoubted habit of command.

“Victor Marbran,” replied the big man, “is Elias van der Spyck & Co., a firm which made millions in the war by trading with the enemy. In every neutral country there were, of course, firms which specialized in importing contraband for the use of the Germans, but van der Spyck & Co. brought the evasion of the blockade to a fine art. They covered up their tracks, however, with such consummate art that we could never bring anything home to them. In fact, it was only after the armistice that we began to learn something of the immense scope of their operations. There was a master brain behind them. But it was never discovered. It strikes me, however, that we are on the right track at last ...”