"Are you sure of it?" asked Jimmy.

"Absolutely certain," said Crouch. "I don't imagine for a moment that the old woman's in league with a gang of German spies; else she would never have shown us up here. For all that, she's not to be trusted further than a first engineer can throw a quoit. That's all the better for us. I don't suppose she'll come back to-night."

"And what about these men, Russell and Valentine?" asked Jimmy. "Who are they, do you think?"

"Valentine may be any one," answered Crouch. "But I've a shrewd suspicion that Russell is Rudolf Stork. Stork has now been in England three days. He has had plenty of time in which to get to London."

"And if he turns up," asked the boy, "what are we to do?"

"If it's necessary, shoot him like a dog," said Crouch, forgetting that he was not on his ship's deck.

For the next half-hour, they systematically searched the whole flat, but could find nothing suspicious. There was an aspect of newness about the place; carpets, curtains, and cushions had evidently come straight from the furnishers, and showed no signs of wear. In an old-fashioned Sheraton bureau were writing and blotting paper, ink and pens; but, the blotting paper was quite spotless, and the pen nibs had never been dipped into the ink.

"There's nothing here," said Crouch. "We shall have to wait for Stork."

And hardly had the words left his lips than a bell rang, somewhere in the room. Jimmy started, and even Crouch carried a hand to the coat pocket that contained his revolver. The moment was one of intense excitement; they were face to face with great events. It was as if the atmosphere of the room was electrified by the strong current of antic.i.p.ation.

"The telephone!" cried Jimmy, pointing to the wall.

In a moment, Crouch had the receiver to his ear. He had the wisdom not to speak, until he had found out who it was who had rung up the unoccupied flat, and this proved to be no less a person than the mysterious "Mr. Valentine," who was speaking from the "Hotel Magnificent" in the Strand. "Are you there?" he asked. "Are you the charwoman?"

Crouch replied at once, in the old woman's squeaky voice.

"I'm Mrs. Wycherley," said he.

"I told you," said the voice, "that you were to expect Mr. Russell this evening. He will probably arrive at about eight o'clock."

"Very well, sir," said Crouch. "The rooms is aired, and all the fires was a-lighted this morning, and everything's that clean you could eat your dinner off the carpet, as sure as my Emily Jane's blood has turned to water."

"Shut up!" cried "Valentine," so loudly that even Jimmy was able to hear. "I've not rung up to hear about Emily Jane. I intended to come round this evening, to meet Mr. Russell on his arrival; but I have to go to Edinburgh at once, on extremely urgent business, and have only just time to catch my train. Can you hear what I say?"

"Bless you, yes, sir," answered Crouch. "It don't make no difference whether it's the butcher or a hundred-weight o' coal, I allus makes use of the telegraph, and I don't take no sauce from the young woman in the middle."

"Then, listen here," said "Valentine." "I'm sending round a messenger-boy with an important sealed letter. On no account whatever are you to let this letter out of your hands, until you give it to Mr.

Russell, the very moment he arrives."

"Valentine," in order to make quite sure that Mrs. Wycherley had heard aright and understood, made Crouch repeat his instructions word for word. That done he rang off, apparently in the greatest haste, no doubt fearing to miss his train.

Captain Crouch was wildly excited. Jamming his white bowler hat well on to the back of his head, he proclaimed that they were hot upon the scent of the gang. Mrs. Wycherley had left him in possession of the key of the flat; and going down to the front door, he waited impatiently for the messenger to arrive.

The messenger-boy had some diffidence about handing over the letter to Crouch, saying that he understood that he was to deliver it to a charwoman. Crouch, however, was not to be denied, and with the sealed letter in his hand returned to Jimmy.

To break the seal and tear open the envelope was the work of a few seconds. The letter was written in German, of which language Crouch and Jimmy knew enough to make out the meaning, though there were one or two words that neither could understand. With the translation of "Valentine's" letter all doubt was dispelled that the unknown "Mr.

Russell" was any one else than Rudolf Stork, the ship's carpenter of the "Harlech."

The letter began with the words "Dear Stork," and continued to the following effect: A sea raid had been planned on the North Coast, against the dockyards of the Forth and Tyne. All German submarines had been warned, with the exception of the U93, whose wireless had been probably by H.M. Destroyer "c.o.c.kroach." The U93 had come north-eastward from the Lizard, had pa.s.sed the Straits of Dover in safety, and was now lying somewhere in the vicinity of the Wellbank lightship, which is a little north of the lat.i.tude of the Tyne.

Immediately on his arrival in London, Stork was to go to Hull, taking the first and fastest train. Thence, he was to put to sea in a fishing smack, the "Marigold," the skipper of which was in the pay of "Valentine." He was to find the U93, and tell her to proceed due east without delay, to meet the German fleet, issuing from the Bight of Heligoland, and which would comprise some of the biggest battle-cruisers ever built: notably, the "Derfflinger," the "Seydlitz," the "Blucher,"

and the "Moltke."

Captain Crouch was a man of iron nerve; but, when he realized the colossal magnitude of the plot with which they were confronted, even he could not control the features of his face. As for Jimmy Burke, his lips were parted, and when he held the letter in his hand, the sheet of paper trembled like a leaf. Scene by scene, the great drama that had opened in the offices of Rosencrantz and Guildenstern unfolded itself before the eyes of those who were something more than mere spectators.

And each scene, it appeared, was more dramatic, more fraught with terrible consequences and possibilities of triumph or disaster, than that which had gone before.

It took Jimmy Burke some time to find his breath. He was so excited that he found it difficult to speak.

"There's not a moment to lose!" he cried. "We must report what we know both to the Admiralty and Scotland Yard."

"We can't leave this place," said Crouch. "Stork may turn up at any minute; it must be nearly eight o'clock already. I'll ring up the Yard, at once."

He went straight to the telephone, where almost immediately he got into communication with the famous headquarters of the London Police. He was informed that a superintendent-detective would be sent at once to Number 758, Edgware Road.

Crouch placed the receiver back upon its rest, and pulled out his watch.

"It's past eight o'clock," said he. "Russell should be here."

It was at that very moment that they heard the sound of footsteps upon the stone staircase without. Crouch hurried to the door and threw it open; and there entered three men, two of whom were young, whilst the other was considerably over sixty.

Both Crouch and Jimmy scanned the face of each man as he entered, and both, with their hands in their pockets, grasped the handles of their revolvers. In spite of the intense excitement of the moment, Jimmy Burke was conscious of a feeling of bitter disappointment, when he saw that not one of these three men was Rudolf Stork.

Each of the two younger men was well over six feet in height, broad of shoulder and deep of chest. They were dressed precisely the same, and wore blue suits, light-coloured overcoats, brown boots and wide-brimmed, black felt hats. As for the older man, he had the appearance of a professor, or some sage of ancient times; there was something about him that might almost be described as druidical. His hair was quite white, very long and somewhat greasy. He had a white beard that reached almost to his waist. His nose was long and aquiline, and his eyes much magnified by a pair of gold-rimmed spectacles. In his hand he carried an ash-plant, so knotted and heavy at the head that it resembled a club.

It was he who was the first to speak, staring at Crouch over the top of his spectacles.

"Pardon me," he observed, in a voice that was exceedingly soft; "pardon me, but I have not the pleasure."

"Nor I," said Captain Crouch.

"I think you must have made a mistake," the old man went on. "My name is Russell--Theophilus Russell--and this flat belongs to me."

"Then," said Crouch, "there must certainly be some mistake. My name is Shakespeare--Melchisedek Shakespeare--and this flat happens to belong to me."

Mr. Russell adjusted his spectacles upon his nose, and looked around the room.

"There should be a woman here," said he; "a Mrs. Wycherley."

"She's gone out," said Crouch.

The old man smiled and pointed with his stick.

"Why, there she is!" he exclaimed. "How strange that I never noticed her before."

He had pointed to the armchair, at the other end of the room, in which Crouch had formerly been seated. The whole thing was so cleverly planned, the old man's voice was so dulcet and confiding, and his expression of surprise so admirably feigned, that Crouch could not resist the wholly natural impulse of turning round, to see for himself whether or not Mrs. Wycherley were there.

His eyes had not left the old man's face for longer than the fraction of a second before there took place a kind of transfiguration which was even more terrible to see than it was surprising.

There had been something about the patriarchal figure of the old, white-bearded man that was gentle, beneficent and charitable. His expression had been that of one who looks upon the world, and all its fooleries and foibles, with the comfortable tolerance of age. On a sudden, this expression changed. His eyes flashed; his brows became knit in a savage frown. At the same time, this transformation extended to his body, which straightened, quivered, and even seemed to grow larger. Before it was possible to guess what he was about to do, or make the slightest movement by way of self-defence, he had raised his heavy ash-plant high above his shoulder, and brought it down with a crashing blow upon the head of Captain Crouch.

The little sea-captain had been taken unawares. Once again had he been fooled. He let out a groan, spun round like a top, and then came down heavily upon the floor.

In so short a s.p.a.ce of time did this calamity occur that Jimmy Burke had barely time to act. He had taken two steps forward, and had got so far as drawing his revolver from his pocket, when he was seized and held fast in the powerful arms of the two younger men. Before he had time to cry out, or even to realize what had happened, he found himself not only with a gag thrust into his mouth, but with both hands handcuffed behind his back.