But the man in front of him hesitated.

"Now that I remember it-"

"Yes," said Tommy eagerly. "What?"

"I don't think it could have anything to do with it. But there was a young lady."

"Yes? A young lady, you say, what was she doing?"

"She was taken faint, sir. A very pleasant young lady. Miss Eileen O'Hara, her name was. A dainty looking lady, not tall, with black hair. Just a little foreign looking."

"Yes?" said Tommy, with even greater eagerness.

"As I was saying, she was taken queer. Just outside Mr. Wilmott's cabin. She asked me to fetch the doctor. I helped her to the sofa, and then went off for the doctor. I was some time finding him, and when I found him and brought him back, the young lady was nearly all right again."

"Oh!" said Tommy.

"You don't think, sir-"

"It's difficult to know what to think," said Tommy noncommittally. "Was this Miss O'Hara travelling alone?"

"Yes, I think so, sir."

"You haven't seen her since you landed?"

"No, sir."

"Well," said Tommy, after a minute or two spent in reflection. `'I think that's all. Thank you, Richards."

"Thank you, sir."

Back at the office of the Detective Agency, Tommy retailed his conversation with Richards to Tuppence who listened attentively.

"What do you think of it, Tuppence?"

"Oh! my dear fellow, we doctors are always sceptical of a sudden faintness! So very convenient. And Eileen as well as O'Hara. Almost too impossibly Irish, don't you think?"

"It's something to go upon at last. Do you know what I am going to do, Tuppence? Advertise for the lady."

"What?"

"Yes. Any information respecting Miss Eileen O'Hara, known to have travelled such and such a ship and such and such a date. Either she'll answer it herself if she's genuine, or someone may come forward to give us information about her. So far, it's the only hope of a clue."

"You'll also put her on her guard, remember."

"Well," said Tommy. "One's got to risk something."

"I still can't see any sense in the thing," said Tuppence, frowning. "If a gang of crooks get hold of the Ambassador's bag for an hour or two, and then send it back, what possible good can it do them? Unless there are papers in it they want to copy, and Mr. Wilmott swears there was nothing of the kind. "

Tommy stared at her thoughtfully.

"You put these things rather well, Tuppence," he said at last. "You've given me an idea."

It was two days later. Tuppence was out to lunch. Tommy, alone in the austere office of Mr. Theodore Blunt, was improving his mind by reading the latest sensational thriller.

The door of the office opened and Albert appeared.

"A young lady to see you, sir. Miss Cicely March. She says she has called in answer to an advertisment."

"Show her in at once," cried Tommy, thrusting his novel into a convenient drawer.

In another minute Albert had ushered in the young lady.

Tommy had just time to see that she was fair haired and extremely pretty when the amazing occurrence happened.

The door through which Albert had just passed out was rudely burst open. In the doorway stood a picturesque figure-a big dark man, Spanish in appearance, with a flaming red tie. His features were distorted with rage, and in his hand was a gleaming pistol.

"So this is the office of Mr. Busybody Blunt," he said in perfect English. His voice was low and venomous. "Hands up at once-or I shoot."

It sounded no idle threat. Tommy's hands went up obediently. The girl, crouched against the wall, gave a gasp of terror.

"This young lady will come with me," said the man. "Yes, you will, my dear. You have never seen me before, but that doesn't matter. I can't have my plans ruined by a silly little chit like you. I seem to remember that you were one of the passengers on the Nomadic. You must have been peering into things that didn't concern you-but I've no intention of letting you blab any secrets to Mr. Blunt here. A very clever gentleman, Mr. Blunt, with his fancy advertisements. But as it happens. I keep an eye on the advertisement columns. That's how I got wise to his little game."

"You interest me exceedingly," said Tommy. "Won't you go on?"

"Cheek won't help you, Mr. Blunt. From now on, you're a marked man. Give up this investigation, and we'll leave you alone. Otherwise-God help you! Death comes swiftly to those who thwart our plans."

Tommy did not reply. He was staring over the intruder's shoulder as though he saw a ghost.

As a matter of fact he was seeing something that caused him far more apprehension than any ghost could have done. Up to now, he had not given a thought to Albert as a factor in the game. He had taken for granted that Albert had already been dealt with by the mysterious stranger. If he had thought of him at all, it was as one lying stunned on the carpet in the outer office.

He now saw that Albert had miraculously escaped the stranger's attention. But instead of rushing out to fetch a policeman in good sound British fashion, Albert had elected to play a lone hand. The door behind the stranger had opened noiselessly, and Albert stood in the aperture enveloped in a coil of rope.

An agonized yelp of protest burst from Tommy, but too late. Fired with enthusiasm, Albert flung a loop of rope over the intruder's head, and jerked him backwards off his feet.

The inevitable happened. The pistol went off with a roar and Tommy felt the bullet scorch his ear in passing, ere it buried itself in the plaster behind him.

"I've got him, sir," cried Albert, flushed with triumph. "I've lassoed him. I've been practicing with a lasso in my spare time, sir. Can you give me a hand? He's very violent."

Tommy hastened to his faithful henchman's assistance, mentally determining that Albert should have no further spare time.

"You damned idiot," he said. "Why didn't you go for a policeman? Owing to this fool's play of yours, he as near as anything plugged me through the head. Whew! I've never had such a near escape."

"Lassoed him in the nick of time, I did," said Albert, his ardor quite undamped. "It's wonderful what those chaps can do on the prairies, sir."

"Quite so," said Tommy, "but we're not on the prairies. We happen to be in a highly civilized city. And now, my dear sir," he added to his prostrate foe. "What are we going to do with you?"

A stream of oaths in a foreign language was his only reply.

"Hush," said Tommy. "I don't understand a word of what you're saying, but I've got a shrewd idea it's not the kind of language to use before a lady. You'll excuse him, won't you, Miss-do you know, in the excitement of this little upset, I've quite forgotten your name?"

"March," said the girl. She was still white and shaken. But she came forward now and stood by Tommy looking down on the recumbent figure of the discomfited stranger. "What are you going to do with him?"

"I could fetch a bobby now," said Albert helpfully.

But Tommy, looking up, caught a very faint negative movement of the girl's head, and took his cue accordingly.

"We'll let him off this time," he remarked. "Nevertheless I shall give myself the pleasure of kicking him downstairs- if it's only to teach him manners to a lady."

He removed the rope, hauled the victim to his feet, and propelled him briskly through the outer office.

A series of shrill yelps was heard and then a thud. Tommy came back, flushed but smiling.

The girl was staring at him with round eyes.

"Did you-hurt him?"

"I hope so," said Tommy. "But these foreigners make a practice of crying out before they're hurt-so I can't be quite sure about it. Shall we come back into my office, Miss March, and resume our interrupted conversation? I don't think we shall be interrupted again."

"I'll have my lasso ready, sir, in case," said the helpful Albert.

"Put it away," ordered Tommy sternly.

He followed the girl into the inner office, and sat down at his desk whilst she took a chair facing him.

"I don't quite know where to begin," said the girl. "As you heard that man say, I was a passenger on the Nomadic. The lady you advertised about, Miss O'Hara, was also on board."

"Exactly," said Tommy. "That we know already, but I suspect you must know something about her doings on board that boat or else that picturesque gentleman would not have been in such a hurry to intervene."

"I will tell you everything. The American Ambassador was on board. One day, as I was passing his cabin, I saw this woman inside, and she was doing something so extraordinary that I stopped to watch. She had a man's boot in her hand-"

"A boot?" cried Tommy excitedly. "I'm sorry, Miss March, go on."

"With a little pair of scissors, she was slitting up the lining. Then she seemed to push something inside. Just at that minute the doctor and another man came down the passage, and immediately she dropped back on the couch and groaned. I waited, and I gathered from what was being said that she had pretended to feel faint. I say pretended-because when I first caught sight of her, she was obviously feeling nothing of the kind."

Tommy nodded.

"Well?"

"I rather hate to tell you the next part. I was-curious. And also I'd been reading silly books, and I wondered if she'd put a bomb or a poisoned needle or something like that in Mr. Wilmott's boot. I know it's absurd-but I did think so. Anyway, next time I passed the empty cabin, I slipped in, and examined the boot. I drew out from the lining a slip of paper. Just as I had it in my hand, I heard the steward coming, and I hurried out so as not to be caught. The folded paper was still in my hand. When I got into my own cabin, I examined it. Mr. Blunt, it was nothing but some verses from the Bible."

"Verses from the Bible?" said Tommy, very much intrigued.

"At least I thought so at the time. I couldn't understand it, but I thought perhaps it was the work of a religious maniac. Anyway, I didn't feel it was worth while replacing it. I kept it without thinking much about it until yesterday when I used it to make into a boat for my little nephew to sail in his bath. As the paper got wet, I saw a queer kind of design coming out all over it. I hastily took it out of the bath, and smoothed it out flat. The water had brought out the hidden message. It was a kind of tracing-and looked like the mouth of a harbor. Immediately after that I read your advertisement."