Mrs. McGillicuddy panted along the platform in the wake of the porter carrying her suitcase. Mrs. McGillicuddy was short and stout, the porter was tall and free-striding. In addition, Mrs. McGillicuddy was burdened with a large quantity of parcels; the result of a day's Christmas shopping. The race was, therefore, an uneven one, and the porter turned the corner at the end of the platform whilst Mrs. McGillicuddy was still coming up the straight.

No.1 Platform was not at the moment unduly crowded, since a train had just gone out, but in the no-man's-land beyond, a milling crowd was rushing in several directions at once, to and from undergrounds, left-luggage offices, tea-rooms, injury offices, indicator boards, and the two outlets, Arrival and Departure, to the outside world.

Mrs. McGillicuddy and her parcels ere buffeted to and fro, but she arrived eventually at the entrance to No.3 platform, and deposited one parcel at her feet whilst she searched her bag for the ticket that would enable her to pass the stern uniformed guardian at the gate.

At that moment, a Voice, raucous yet refined, burst into speech over her head.

"The train standing at Platform 3," the Voice told her, "is the 4.50 for Brackhampton, Milchester, Waverton, Carvil Junction, Roxeter and stations to Chadmouth. Passengers for Brackhampton and Milchester travel at the rear of the train. Passengers for Vanequay change at Roxeter." The Voice shut itself off with a click, and then reopened conversation by announcing the arrival at Platform 9 of the 4.35 from Birmingham and Wolverhampton.

Mrs. McGillicuddy found her ticket and presented it. The man clipped it, murmured: "On the right – rear portion."

Mrs. McGillicuddy padded up the platform and found her porter, looking bored and staring into space, outside the door of a third-class carriage.

"Here you are, lady."

"I'm travelling first-class," said Mrs. McGillicuddy.

"You didn't say so," grumbled the porter. His eyes swept her masculine-looking pepper-and-salt tweet coat disparagingly.

Mrs. McGillicuddy, who had said so, did not argue the point. She was sadly out of breath.

The porter retrieved the suitcase and marched with it to the adjoining coach where Mrs. McGillicuddy was installed in solitary splendour. The 4.50 was not much patronised, the first-class clientele preferring either the faster morning express, or the 6.40 with dining-car. Mrs. McGillicuddy handed the porter his tip which he received with disappointment, clearly considering it more applicable to third-class than to first-class travel. Mrs. McGillicuddy, though prepared to spend money on comfortable travel after a night journey from the North and a day's feverish shopping, was at no time an extravagant tipper.

She settled herself back on the plush cushions with a sigh and opened a magazine. Five minutes later, whistles blew, and the train started. The magazine slipped from Mrs. McGillicuddy's hand, her head dropped sideways, three minutes later she was asleep. She slept for thirty-five minutes and awoke refreshed. Resettling her hat which had slipped askew, she sat up and looked out of the window at what she could see of the flying countryside. It was quite dark now, a dreary misty December day - Christmas was only five days ahead. London had been dark and dreary; the country was no less so, though occasionally rendered cheerful with its constant clusters of lights as the train flashed through towns and stations.

"Serving last tea now," said an attendant, whisking open the corridor door like a jinn. Mrs. McGillicuddy had already partaken of tea at a large department store. She was for the moment amply nourished. The attendant went on down the corridor uttering his monotonous cry. Mrs. McGillicuddy looked up at the rack where her various parcels reposed, with a pleased expression. The face towels had been excellent value and just what Margaret wanted, the space gun for Robby and the rabbit for Jean were highly satisfactory, and that evening coatee was just the thing she herself needed, warm but dressy. The pullover for Hector, too…her mind dwelt with approval on the soundness of her purchases.

Her satisfied gaze returned to the window, a train travelling in the opposite direction rushed by with a screech, making the windows rattle and causing her to start. The train clattered over points and passed through a station.

Then it began suddenly to slow down, presumably in obedience to a signal. For some minutes it crawled along, then stopped, presently it began to move forward again. Another up-train passed them, though with less vehemence than the first one. The train gathered speed again. At that moment another train, also on a down-line, swerved inwards towards them, for a moment with almost alarming effect. For a time the two trains ran parallel, now one gaining a little, now the other. Mrs. McGillicuddy looked from her window through the windows of the parallel carriages. Most of the blinds were down, but occasionally the occupants of the carriages were visible. The other train was not very full and there were many empty carriages.

At the moment when the two trains gave the illusion of being stationary, a blind in one of the carriage flew up with a snap. Mrs. McGillicuddy looked into the lighted first-class carriage that was only a few feet away.

Then she drew her breath in with a gasp and half-rose to her feet.

Standing with his back to the window and to her was a man. His hands were round the throat of a woman who faced him, and he was slowly, remorselessly, strangling her. Her eyes were starting from their sockets, her face was purple and congested. As Mrs. McGillicuddy watched, fascinated, the end came; the body went limp and crumpled in the man's hands.

At the same moment, Mrs. McGillicuddy's train slowed down again and the other began to gain speed. It passed forward and a moment or two later it had vanished from sight.

Almost automatically Mrs. McGillicuddy's hand went up to the communication cord, then paused, irresolute. After all, what use would it be ringing the cord of the train in which she was travelling? The horror of what she had seen at such close quarters, and the unusually circumstances, made her feel paralysed. Some immediate action was necessary - but what?

The door of her compartment was drawn back and a ticket collector said: "Ticket, please."

Mrs. McGillicuddy turned to him with vehemence.

"A woman has been strangled," she said. "In a train that just passed. I saw it."

The ticket collector looked at her doubtfully.

"I beg your pardon, madam?"

"A man strangled a woman! In a train. I saw it – through there." She pointed to the window.

The ticket collector looked extremely doubtful.

"Strangled?" he said disbelievingly.

"Yes, strangled! I saw it, I tell you. You must don something at once!"

The ticket collector coughed apologetically.

"You don't think, madam, that you may have had a little nap and - er - " he broke off tactfully.

"I have had a nap, but if you think this was a dream, you're quite wrong. I saw it, I tell you."

The ticket collector's eyes dropped to the open magazine lying on the seat. On the exposed page was a girl being strangled whilst a man with a revolver threatened the pair from an open doorway.

He said persuasively: "Now don't you think, madam, that you'd been reading an exciting story, and that you just dropped off, and awaking a little confused –"

Mrs. McGillicuddy interrupted him.

"I saw it," she said. "I was as wide awake as you are. And I looked out of the window into the window of the train alongside, and a man was strangling a woman. And what I want to know is, what are you going to do about it?"

"Well - madam –"

"You're going to do something, I suppose?"

The ticket collector sighed reluctantly and glanced at his watch.

"We shall be in Brackhampton in exactly seven minutes. I'll report what you've told me. In what direction was the train you mention going?

"This direction, of course. You don't suppose I'd have been able to see all this if a train had flashed past going in the other direction?"

The ticket collector looked as though he thought Mrs. McGillicuddy was quite capable of seeing anything anywhere as the fancy took her. But her remained polite.

"You can rely on me, madam," he said. "I will report your statement. Perhaps I might have your name and address - just in case…"

Mrs. McGillicuddy gave him the address where she would be staying for the next few days and her permanent address in Scotland, and he wrote them down. Then he withdrew with the air of a man who has done his duty and dealt successfully with a tiresome member of the travelling public.

Mrs. McGillicuddy remained frowning and vaguely unsatisfied. Would the ticket collector really report her statement? Or had he just been soothing her down? There were, she supposed vaguely, a lot of elderly women travelling around, fully convinced that they had unmasked communist plots, were in danger of being murdered, saw flying saucers and secret space ships, and reported murders that had never taken place. If the man dismissed her as one of those…

The train was slowing down now, passing over points and running through the bright lights of a large town.

Mrs. McGillicuddy opened her handbag, pulled out a receipted bill which was all she could find, wrote a rapid note on the back of it with her ball-point pen, put it into a spare envelope that she fortunately happened to have, stuck the envelope down and wrote on it.

The train drew slowly into a crowded platform. The usual ubiquitous Voice was intoning:

"The train now arriving at Platform 1 is the 5.38 for Milchester, Waverton, Roxeter, and stations to Chadmouth. Passengers for Market Basing take the train now waiting at No.3 platform. No.1 bay for stopping train to Carbury."

Mrs. McGillicuddy looked anxiously along the platform. So many passengers and so few porters. Ah, there was one! She hailed him authoritatively.

"Porter! Please take this at once to the Stationmaster's office."

She handed him the envelope, and with it a shilling.

Then, with a sigh, she leaned back. Well, she had done what she could. Her mind lingered with an instant's regret on the shilling…. Sixpence would really have been enough….

Her mind went back to the scene she had witnessed. Horrible, quite horrible…. She was a strong-nerved woman, but she shivered. What a strange - what a fantastic thing to happen to her, Elspeth McGillicuddy! If the blind of the carriage had not happened to fly up…. But that, of course, was Providence.

Providence had willed that she, Elspeth McGillicuddy, should be a witness of the crime. Her lips set grimly.

Voices shouted, whistles blew, doors were banged shut. The 5.38 drew slowly out of Brackhampton station. An hour and five minutes later it stopped at Milchester.

Mrs. McGillicuddy collected her parcels and her suitcase and got out. She peered up and down the platform. Her mind reiterated its former judgment: Not enough porters. Such porters as there were seemed to be engaged with mail bags and luggage vans. Passengers nowadays seemed always expected to carry their own cases. Well, she couldn't carry her suitcase and her umbrella and all her parcels. She would have to wait. In due course she secured a porter.

"Taxi?"

"There will be something to meet me, I expect."

Outside Milchester station, a taxi-driver who had been watching the exit came forward. He spoke in a soft local voice.

"Is it Mrs. McGillicuddy? For St. Mary Mead?"

Mrs. McGillicuddy acknowledged her identity. The porter was recompensed, adequately if not handsomely. The car, with Mrs. McGillicuddy, her suitcase, and her parcels drove off into the night. It was a nine-mile drive. Sitting bolt upright in the car, Mrs. McGillicuddy was unable to relax. Her feelings yearned for expression. At last the taxi drove along the familiar village street and finally drew up at its destination; Mrs. McGillicuddy got out and walked up the brick path to the door. The driver deposited the cases inside as the door was opened by an elderly main. Mrs. McGillicuddy passed straight through the hall to where, at the open sitting-room door, her hostess awaited her; an elderly frail old lady.

"Elspeth!"

"Jane!"

They kissed and, without preamble or circumlocution, Mrs. McGillicuddy burst into speech.

"Oh, Jane!" she wailed. "I've just seen a murder!"