"Oh, thank you, thank you!" said Bawdrey gratefully. "I don't care a hang what it costs, what your fees are, Mr. Headland. So long as you run those two to earth, and get hold of the horrible stuff, whatever it is, that they are using, I'll pay any price in the world, and count it cheap as compared with the life of my dear old dad. When can you take hold of the case? Now?"

"I'm afraid not. Mysterious things like this require a little thinking over. Suppose we say to-morrow noon? Will that do?"

"I suppose it must, although I should have liked to take you back with me. Every moment's precious at a time like this. But if it must be delayed until to-morrow—well, it must, I suppose. But I'll take jolly good care that nobody gets a chance to come within touching distance of the pater—bless him!—until you do come, if I have to sit on the mat before his door until morning. Here's the address on this card, Mr. Headland. When and how shall I expect to see you again? You'll use an alias, of course?"

"Oh, certainly! Had you any old friend in your college days whom your father only knew by name and who is now too far off for the imposture to be discovered?"

"Yes. Jim Rickaby. We were as inseparable as the Siamese twins in our undergrad days. He's in Borneo now. Haven't heard from him in a dog's age."

"Couldn't be better," said Cleek. "Then 'Jim Rickaby' let it be. You'll get a letter from him first thing in the morning saying that he's back in England, and about to run down and spend the week-end with you. At noon he will arrive, accompanied by his Borneo servant, named—er—Dollops. You can put the 'blackie' up in some quarter of the house where he can move about at will without disturbing any of your own servants, and can get in and out at all hours; he will be useful, you know, in prowling about the grounds at night and ascertaining if the lady really does go to bed when she retires to her room. As for 'Jim Rickaby' himself—well, you can pave the way for his operations by informing your father, when you get the letter, that he has gone daft on the subject of old china and curios and things of that sort, don't you know."

"What a ripping idea!" commented young Bawdrey. "I twig. He'll get chummy with you, of course, and you can lead him on and adroitly 'pump' him regarding her, and where she keeps her keys and things like that. That's the idea, isn't it?"

"Something of that sort. I'll find out all about her, never fear," said Cleek in reply. Then they shook hands and parted, and it was not until after young Bawdry had gone that either he or Narkom recollected that Cleek had overlooked telling the young man that Headland was not his name.

"Oh, well, it doesn't matter. Time enough to tell him that when it comes to making out the cheque," said Cleek, as the superintendent remarked upon the circumstance. Then he pushed back his chair and walked over to the window, and stood looking silently out upon the flowing river. Narkom did not disturb his reflections. He knew from past experience, as well as from the manner in which he took his lower lip between his teeth and drummed with his finger-tips upon the window-ledge, that some idea relative to the working out of the case had taken shape within his mind, and so, with the utmost discretion, went on with his tea and refrained from speaking. Suddenly Cleek turned. "Mr. Narkom, do me a favour, will you? Look me up a copy of Holman's 'Diseases of the Kidneys' when you go back to town. I'll send Dollops round to the Yard to-night to get it."

"Right you are," said Narkom, taking out his pocket-book and making a note of it. "But, I say, look here, my dear fellow, you can't possibly believe that it's anything of that sort—anything natural, I mean—in the face of what we've heard?"