Lord Morradale, who kept up honest, country-squire habits even in London, had gone to bed when Hetherwick and Mapperley arrived at his house, but he lost little time in making an appearance, in pyjamas and dressing-gown, and listened eagerly to Hetherwick's account of the recent transactions.  
"Force!" he muttered, nodding his head at each point of the story. "Force! got it out of her by force. That is, if the order's genuine."
 
Mapperley produced the sheet of paper, which he had filched under the caretaker's eyes, and silently handed it over.
 
"Oh, that's Madame Listorelle's handwriting!" exclaimed Lord Morradale. "Hers, without doubt. Difficult to imitate, of course. Oh, yes—hers! Well, that proves what I've just said, Mr. Hetherwick—force! She's in their power—with the young lady, Miss—Miss—Featherstone, to be sure—and they've made her write that. Next, they'll make her write an order on the Imperial Safe Deposit. We must be beforehand with them there. Early—early as possible in the morning. Meet me at Matherfield's—I think he's pretty keen. Bless me! what a pack of villains! Now I wonder where, in all London, these unfortunate ladies are?"
 
"That's precisely what all this ought to help us to find out," remarked Hetherwick. "I'm not so much concerned about the valuables these men are after as about the safety of——"
 
Lord Morradale gave him a quick, understanding glance.
 
"Of Miss Featherstone, eh?" he said. "I see—I see! And I'm concerned, too, about Madame Listorelle. Well, this, as you say, ought to help. But look here—we must be cautious—very cautious! We mustn't let Matherfield—you know what the police are—we mustn't let him be too precipitate. Probably—if a man comes to the safe place, he'll go away from it to where these scoundrels are. We must follow—follow!"
 
"I agree," said Hetherwick.
 
"Nine o'clock, then, at Matherfield's," concluded his lordship. "And may we have a strong scent, a rousing one, and a successful kill!"
 
With this bit of sporting phraseology in their ears, Hetherwick and Mapperley returned to the Middle Temple and retired for the rest of the night, one to bed, the other to a shake-down on the sitting-room sofa. But when Hetherwick's alarum clock awoke him at seven-thirty and he put his head into the next room to rouse the clerk, he found that Mapperley had vanished. The cushions, rugs, and blankets with which he had made himself comfortable for the night were all neatly folded and arranged—on the topmost was pinned a sheet of brief-paper, with a message scrawled in blue pencil.
 
 
You won't want me this morning; off on an important notion of my own. Look out for message from me about noon.
 
M.
 
 
Muttering to himself that he hadn't the least idea as to what his clerk was about, Hetherwick made a hurried toilet, and an equally hurried breakfast, and hastened away to meet Matherfield and Lord Morradale. He found these two together, and with them a quiet, solemn-faced individual, clad in unusually sombre garments, whom Matherfield introduced as Detective-Sergeant Quigman. Matherfield went straight to business.
 
"His lordship's just told me of your adventure last night, Mr. Hetherwick," he said, "and I'm beginning to get a sort of forecast of what's likely to happen. It was, of course, Baseverie who went to madame's flat last night—that's settled. But what do you suppose he went for?"
 
"Can't say that I've worked that out," answered Hetherwick, with a glance at the others. "But I imagine that he went there to get, say, certain keys—having forced Madame Listorelle to tell him where they were. The keys of her safe at the Deposit place, I should think."
 
"No!" replied Matherfield, shaking his head knowingly, and with a sly smile at Quigman. "No, not that. I'll tell you what he went for—a very simple thing. He went to get some of Madame's private notepaper! He knew well enough that if he was to take an order on that Safe Deposit to allow the bearer access to Madame's safe it would have to be what the French, I believe, call en régle—eh? Written on her own notepaper in her own handwriting, and so on. See?"
 
"I think you're right, and I think he got it," said Hetherwick. "A drawer in her desk containing boxes of stationery had been pulled out, and some of its contents lay about the desk. As a matter of fact, though I scarcely know why I did it, I put some paper and some envelopes in my pocket—here they are! I had a faint idea that they might be useful—somehow."
 
"Well, that's the notion, depend on it," asserted Matherfield, glancing at the paper which Hetherwick produced. "I've no doubt that somebody, representing Madame Listorelle, and bearing an authorization from her, written on her notepaper in her own writing, will present himself at the Imperial Safe Deposit this morning. But—it won't be Baseverie! And it won't be Ambrose!"
 
"A stranger, eh?" suggested Hetherwick.
 
"We shall see. Now," continued Matherfield, glancing at the clock, "we'll be off to the scene of operations. This Imperial Safe Deposit is in Kingsway—Holborn end—and very fortunately situated for our job, being close to the Tube station; there'll be lots of people about there, and we shan't attract attention. And this is the way of it—his lordship and myself will go into the Safe Deposit, see the people in charge, explain matters, and get them to tell us at once if and when the expected ambassador arrives. We shall let him——"
 
"Or her," interrupted Quigman solemnly.
 
"Just so, my lad—it might be a she," assented Matherfield. "Quite likely! We shall let him or her get what is wanted from the safe and go away, closely followed by all four of us. While Lord Morradale and I are inside, you and Quigman, Mr. Hetherwick, will be outside, talking, casually. When we come out—and you'll both keep a sharp watch on the entrance hall—I'll give you the office as to the particular person we're following, and wherever that person goes, you two will go. But don't come near us—we'll keep one side of the street, you the other. If the person takes to a cab or a bus—well, we'll have to do the same. But I've reasons for thinking he or she will stick to his feet!"
 
"How do we go?—all together?" asked Hetherwick. "Because—it's a mere idea—how do you know, Matherfield, that these people—there would appear to be more than one concerned—aren't keeping an eye on you?"
 
"I've thought of that," answered Matherfield. "No—we're all going separately. It's now nine-fifteen. That Imperial Safe Deposit doesn't open its doors till ten—nobody can get in there until that time, anyway. We all four go out of this office on our own hook. Each takes his own method of getting to the top of Kingsway. As soon as I get there, I go straight in and ask for the manager. As soon as Lord Morradale gets there, he follows suit—he and I forgather in the manager's room. As for you two, go how you like—fly, if it suits you—or wander round the side streets. But—you meet right opposite the Safe Deposit entrance at precisely ten o'clock, and under pretence of casual meeting and conversation keep your eyes on it, noticing everybody who goes in and comes out. That clear? Then we all clear out—one by one."
 
Outside, and left to his own devices, Hetherwick walked a little way and then hailed a taxi-cab. He gave his driver a confidential smile.
 
"You can just help me to employ forty minutes," he said, as he got in. "Drive round—anywhere you like—up and down—as long as you put me down at the corner of the Holborn Restaurant at precisely t............