He opened it in his usual neat, unhurried fashion. The printed words stood out clearly.

"To London."

"Très bien, Monsieur. How far are you going?"

At the Tokatlian, Hercule Poirot asked for a room with bath. Then he stepped over to the concierge's desk and inquired for letters.

"First."

Poirot glanced at the clock again. It was ten minutes to eight. "I have time to dine?"

"Assuredly, Monsieur. There is no difficulty this time of year. The trains are almost empty. First-class or second?"

There were three waiting for him and a telegram. His eyebrows rose a little at the sight of the telegram. It was unexpected.

"At nine o'clock, Monsieur."

"Bien, Monsieur. I will get you a ticket to London and reserve your sleeping car accommodation in the Stamboul-Calais coach."

"Voilà ce qui est embêtant," murmured Poirot vexedly. He glanced up at the clock. "I shall have to go on tonight," he said to the concierge. "At what time does the Simplon Orient leave?"

"Can you get me a sleeper?"

"Development you predicted in Kassner Case has come unexpectedly please return immediately."

"Yes. I have just asked them to get me a sleeper. It was my intention to remain here some days, but I have received a telegram recalling me to England on important business."

"Splendid! I, too. That is to say, I go as far as Lausanne, where I have affairs. You travel on the Simplon-Orient, I presume?"

"Tonight."

'M. Bouc."

The little Belgian nodded. He went over and cancelled his room order and crossed the hall to the restaurant.

As he was giving his order to the waiter a hand was placed on his shoulder.

The speaker was a short, stout elderly man, his hair cut en brosse. He was smiling delightedly.

"But assuredly, Monsieur."

"You find yourself far from home, mon cher," said M. Bouc.

"Ah! And you return home -- when?"

M. Bouc was a Belgian, a director of the Compagnie Internationale des Wagons Lits, and his acquaintance with the former star of the Belgian Police Force dated back many years.

Poirot sprang up.

"A little affair in Syria."

"Ah! mon vieux, but this is an unexpected pleasure," said a voice behind him.

'M. Poirot."

"Ah!" sighed M. Bouc. "Les affaires -- les affaires! But you -- you are at the top of the tree nowadays, mon vieux!"

Bouc laughed.

Hercule Poirot addressed himself to the task of keeping his moustaches out of the soup.

"Some little success I have had, perhaps." Hercule Poirot tried to look modest but failed signally.

"We will meet later," he said.

These two sat at a table not far away. The younger was a likeable-looking man of thirty, clearly an American. It was, however, not he but his companion who had attracted the little detective's attention.

That difficult task accomplished, he glanced round him whilst waiting for the next course. There were only about half a dozen people in the restaurant, and of those half-dozen there were only two that interested Hercule Poirot.

He was a man of between sixty and seventy. From a little distance he had the bland aspect of a philanthropist. His slightly bald head, his domed forehead, the smiling mouth that displayed a very white set of false teeth, all seemed to speak of a benevolent personality. Only the eyes belied this assumption. They were small, deep set and crafty. Not only that. As the man, making some remark to his young companion, glanced across the room, his gaze stopped on Poirot for a moment, and just for that second there was a strange malevolence, and unnatural tensity in the glance.

Then he rose.

"To tell you the truth, my friend, I did not care for him. He produced on me an unpleasant impression. And you?"

"They are Americans," said M. Bouc.

When Poirot rejoined his friend in the lounge, the other two men were just leaving the hotel. Their luggage was being brought down. The younger was supervising the process. Presently he opened the glass door and said: "Quite ready now, Mr. Ratchett."

The elder man grunted an assent and passed out.

"When he passed me in the restaurant," he said at last, "I had a curious impression. It was as though a wild animal -- an animal savage, but savage! you understand -- had passed me by."

"Pay the bill, Hector," he said.

"Assuredly they are Americans. I meant what did you think of their personalities?"

"And the other?"

"The young man seemed quite agreeable."

"Eh bien," said Poirot. "What do you think of those two?"

Hercule Poirot was a moment before replying.

His voice was slightly husky in tone. It had a queer, soft, dangerous quality.

"And yet he looked altogether of the most respectable."

"Well," said M. Bouc cheerfully. "It may be so. There is much evil in the world."

"It is extraordinary, Monsieur," he said to Poirot. "There is not one first-class sleeping berth to be had on the train."

"That respectable American gentleman."

At that moment the door opened and the concierge came towards them. He looked concerned and apologetic.

"You are fanciful, mon vieux," said M. Bouc.

"It may be so. But I could not rid myself of the impression that evil had passed me by very close."

"Précisément! The body -- the cage -- is everything of the most respectable -- but through the bars, the wild animal looks out."

"Comment?" cried M. Bouc. "At this time of year? Ah, without doubt there is some party of journalists -- of politicians --?"

"Well, well," M. Bouc turned to Poirot. "Have no fear, my friend. We will arrange something. There is always one compartment -- the No. 16, which is not engaged. The conductor sees to that!" He smiled, then glanced up at the clock. "Come," he said, "it is time we started."

"That respectable American gentleman?"

"I don't know, sir," said the concierge, turning to him respectfully. "But that's how it is."

He called to the porters and they wheeled their load half-way along the carriage on which the tin plates proclaimed its destination:

M. Bouc made a clicking sound of annoyance.

"No, Monsieur. It is only chance. It just happens that many people have elected to travel tonight."

ISTANBUL TRIESTE CALAIS

"You are full up tonight, I hear?"

"Good evening, Monsieur. Your compartment is the No. 1."

"But yes, Monsieur. As I told you, we are full -- full -- everywhere."

"It is taken, Monsieur."

A glance of understanding passed between them, and the conductor smiled. He was a tall, sallow man of middle age.

"But what passes itself?" demanded M. Bouc angrily. "There is a conference somewhere? It is a party?"

"What? The No. 16?"

"All the same, you must find room for this gentleman here. He is a friend of mine. He can have the No. 16."

"It is incredible, Monsieur. All the world elects to travel tonight!"

At the station M. Bouc was greeted with respectful empressement by the brown-uniformed Wagon Lit conductor.

"Do not distress yourself, my friend," said Poirot. "I must travel in an ordinary carriage."

"No. 7 berth -- a second-class. The gentleman has not yet come, and it is four minutes to nine."

"A name of good omen," said Poirot. "I read my Dickens. M. Harris, he will not arrive."

"Là, là, that is awkward," said M. Bouc.

"But it is a lady's berth. There is already a German woman in the compartment -- a lady's maid."

"At Belgrade," he said, "there will be the slip coach from Athens. There will also be the Bucharest-Paris coach -- but we do not reach Belgrade until tomorrow evening. The problem is for tonight. There is no second-class berth free?"

"Well, then --"

"It is true," said the man, "that there is one passenger who has not yet arrived." He spoke slowly with hesitation.

"There is a second-class berth, Monsieur --"

"An Englishman," the conductor consulted his list. "A M. Harris."

"Who is it?"

"But speak then?"

"Not at all. Not at all." He turned once more to the conductor. "Everyone has arrived?"

"As Monsieur pleases," said the conductor. He spoke to Poirot's porter, directing him where to go.

Poirot passed along the corridor, a somewhat slow progress, as most of the people travelling were standing outside their carriages.

"Put Monsieur's luggage in No. 7," said M. Bouc. "If this M. Harris arrives we will tell him that he is too late -- that berths cannot be retained so long -- we will arrange the matter one way or another. What do I care for a M. Harris?"

His polite "Pardons" were uttered with the regularity of clockwork. At last he reached the compartment indicated. Inside it, reaching up to a suitcase, was the tall young American of the Tokatlian.

"Excuse me," he said. "I think you've made a mistake." Then, laboriously in French, "Je crois que vous avez un erreur."

Then he stood aside the steps to let Poirot enter the train. "Tout à fait au bout, Monsieur," he called. "The end compartment but one."

He frowned as Poirot entered.

Poirot replied in English. "You are Mr. Harris?"

"No, my name is MacQueen. I --"

But at that moment the voice of the Wagon Lit conductor spoke from over Poirot's shoulder. An apologetic, rather breathless voice.

"There is no other berth on the train, Monsieur. The gentleman has to come in here."

The conductor emerged from the compartment, having swung the suitcases up on to the racks.

He was hauling up the corridor window as he spoke and began to lift in Poirot's luggage.

"A phenomenon I have seldom seen," he said cheerfully. "A Wagon Lit conductor himself puts up the luggage! It is unheard of!"

Poirot noticed the apology in his tone with some amusement. Doubtless the man had been promised a good tip if he could keep the compartment for the sole use of the other traveller. However, even the most munificent of tips lose their effect when a director of the company is on board and issues his orders.

"Voilà Monsieur," he said. "All is arranged. Yours is the upper berth, the number 7. We start in one minute."

He hurried off down the corridor. Poirot reentered the compartment.

His fellow traveller smiled. He had evidently got over his annoyance -- had probably decided that it was no good to take the matter other than philosophically. "The train's remarkably full," he said.

There was a sudden jerk. Both men swung round to the window, looking out at the long, lighted platform as it slid slowly past them.

"You are too amiable --"

"Not exactly. You see --"

"No, no," protested Poirot. "I would not deprive you --"

"We're off," said MacQueen.

"It is for one night only," explained Poirot. "At Belgrade --"

"That's all right --"

"Oh, I see. You're getting out at Belgrade --"

The Orient Express had started on its three-days' journey across Europe.

Outside a voice shouted. "En voiture."

"I say, sir," said the young man suddenly, "if you'd rather have the lower berth -- easier, and all that -- well, that's all right by me."

But they were not quite off. The whistle blew again.

Polite protests on both sides.

A whistle blew, there was a long, melancholy cry from the engine. Both men stepped out into the corridor.