"Suggestible—it is in that word that the mystery of Mr. Cust consists!"

"It was not enough for you, Mr. Clarke, to devise this plan of a series to distract attention from a single crime. You had also to have a stalking horse."

"I think the idea first originated in your mind as the result of a chance encounter in a city coffee den with this odd personality with his bombastic Christian names. You were at that time turning over in your mind various plans for the murder of your brother."

"Really? And why?"

"Because you were seriously alarmed for the future. I do not know whether you realize it, Mr. Clarke, but you played into my hands when you showed me a certain letter written to you by your brother. In it he displayed very clearly his affection and absorption in Miss Thora Grey. His regard may have been a paternal one—or he may have preferred to think it so. Nevertheless, there was a very real danger that on the death of your sister-in-law he might, in his loneliness, turn to this beautiful girl for sympathy and comfort and it might end—as so often happens with elderly men—in his marrying her. Your fear was increased by your knowledge of Miss Grey. You are, I fancy, an excellent, if somewhat cynical judge of character. You judged, whether correctly or not, that Miss Grey was a type of young woman 'on the make.' You had no doubt that she would jump at the chance of becoming Lady Clarke."

"Your brother was an extremely healthy and vigorous man. There might be children and your chance of inheriting your brother's wealth would vanish."

"You have been, I fancy, in essence a disappointed man all your life. You have been the rolling stone—and you have gathered very little moss. You were particularly jealous of your brother's wealth."

"I repeat then that, turning over various schemes in your mind, your meeting with Mr. Cust gave you an idea. His bombastic Christian names, his account of his epileptic seizures and of his headaches, his whole shrinking and insignificant personality, struck you as fitting him for the tool you wanted. The whole alphabetical plan sprang into your mind—Cust's initials—the fact that your brother's name began with a C and that he lived at Churston were the nucleus of the scheme. You even went so far as to hint to Cust at his possible end—though you could hardly hope that that suggestion would bear the rich fruit that it did."

"Your arrangements were excellent. In Cust's name you wrote for a large consignment of hosiery to be sent to him. You yourself sent a number of A.B.C.'s looking like a similar parcel. You wrote to him—a typed letter purporting to be from the same firm offering him a good salary and commission. Your plans were so well laid beforehand that you typed all the letters that were sent subsequently, and then presented him with the machine on which they had been typed."

"You had now to look about for two victims whose names began with A and B respectively and who lived at places also beginning with those same letters."

"You hit on Andover as quite a likely spot and your preliminary reconnaissance there led you to select Mrs. Ascher's shop as the scene of the first crime. Her name was written clearly over the door, and you found by experiment that she was usually alone in the shop. Her murder needed nerve, daring and reasonable luck."

"For the letter B you had to vary your tactics. Lonely women in shops might conceivably have been warned. I should imagine that you frequented a few cafйs and teashops, laughing and joking with the girls there and finding out whose name began with the right letter and who would be suitable for your purpose."

"In Betty Barnard you found just the type of girl you were looking for. You took her out once or twice, explaining to her that you were a married man, and that outings must therefore take place in a somewhat hole-and-corner manner."

"Then, your preliminary plans completed, you set to work! You sent the Andover list to Cust, directing him to go there on a certain date and you sent off the first A.B.C. letter to me."

"On the appointed day, you went to Andover—and killed Mrs. Ascher—without anything occurring to damage your plans."

"Murder No. 1 was successfully accomplished."

"For the second murder, you took the precaution of committing it, in reality, the day before. I am fairly certain that Betty Barnard was killed well before midnight on the 24th July."

"We now come to murder No. 3—the important—in fact, the real murder from your point of view."

"And here a full measure of praise is due to Hastings, who made a simple and obvious remark to which no attention was paid."

"He suggested that the third letter went astray intentionally. And he was right! . . ."

"In that one simple fact lies the answer to the question that has puzzled me so all along. Why were the letters addressed in the first place to Hercule Poirot, a private detective, and not to the police?"

"Erroneously I imagined some personal reason."

"Not at all! The letters were sent to me because the essence of your plan was that one of them should be wrongly addressed and go astray—but you cannot arrange for a letter addressed to the Criminal Investigation Department of Scotland Yard to go astray! It is necessary to have a private address. You chose me as a fairly well-known person, and a person who was sure to take the letters to the police—and also, in your rather insular mind, you enjoyed scoring off a foreigner."

"You addressed your envelope very cleverly—Whitehaven—Whitehorse—quite a natural slip. Only Hastings was sufficiently perspicacious to disregard subtleties and go straight for the obvious!"

"Of course the letter was meant to go astray! The police were to be set on the trail only when the murder was safely over. Your brother's nightly walk provided you with the opportunity. And so successfully had the A.B.C. terror taken hold on the public mind that the possibility of your guilt never occurred to anyone."

"After the death of your brother, of course, your object was accomplished. You had no wish to commit any more murders. On the other hand, if the murders stopped without reason, a suspicion of truth might come to someone."

"Your stalking horse, Mr. Cust, had so successfully lived up to his role of the invisible—because insignificant—man, that so far no one had noticed that the same person had been seen in the vicinity of the three murders! To your annoyance, even his visit to Combeside had not been mentioned. The matter had passed completely out of Miss Grey's head."

"Always daring, you decided that one more murder must take place but that this time the trail must be well blazed."

"You selected Doncaster for the scene of operations."

"Your plan was very simple. You yourself would be on the scene in the nature of things. Mr. Cust would be ordered to Doncaster by his firm. Your plan was to follow him round and trust to opportunity. Everything fell out well. Mr. Cust went to a cinema. That was simplicity itself. You sat a few seats away from him. When he got up to go, you did the same. You pretended to stumble, leaned over and stabbed a dozing man in the row in front, slid the A.B.C. on to his knees and managed to collide heavily with Mr. Cust in the darkened doorway, wiping the knife on his sleeve and slipping it into his pocket."

"You were not in the least at pains to choose a victim whose name began with D. Anyone would do! You assumed—and quite rightly—that it would be considered to be a mistake. There was sure to be someone whose name began with D not far off in the audience. It would be assumed that he had been intended to be the victim."