Inspector Chippenfield, who had come into prominence in the newspapers as the man who had caught the gang who had stolen Lady Gladville's jewels—which included the most costly pearl necklace in the world—was placed in charge of the case. It was to his success in this famous case that he owed his promotion to Inspector. He had the assistance of his subordinate, Detective Rolfe. So generous were the newspaper references to the acumen of these two terrors of the criminal classes that it was to be assumed that anything which inadvertently escaped one of them would be pounced upon by the other.

On the morning after the discovery of the murdered man's body, the two officers made their way to Tanton Gardens from the Hampstead tube station. Inspector Chippenfield was a stout man of middle age, with a red face the colour of which seemed to be accentuated by the daily operation of removing every vestige of hair from it. He had prominent grey eyes with which he was accustomed to stare fiercely when he desired to impress a suspected person with what some of the newspapers had referred to as "his penetrating glance." His companion, Rolfe, was a tall well-built man in the early thirties. Like most men in a subordinate position, Rolfe had not a high opinion of the abilities of his immediate superiors. He was sure that he could fill the place of any one of them better than it was filled by its occupant. He believed that it was the policy of superiors to keep junior men back, to stand in their light, and to take all the credit for their work. He was confident that he was destined to make a name for himself in the detective world if only he were given the chance.

When Inspector Chippenfield had visited Riversbrook the previous afternoon, Rolfe had not been selected as his assistant. A careful inspection of the house and especially of the room in which the tragedy had been committed had been made by the inspector. He had then turned his attention to the garden and the grounds surrounding the house.

Whatever he had discovered and what theories he had formed were not disclosed to anyone, not even his assistant. He believed that the proper way to train a subordinate was to let him collect his own information and then test it for him. This method enabled him to profit by his subordinate's efforts and to display a superior knowledge when the other propounded a theory by which Inspector Chippenfield had also been misled.

When they arrived at the house in which the crime had been committed, they found a small crowd of people ranging from feeble old women to babies in arms, and including a large proportion of boys and girls of school age, collected outside the gates, staring intently through the bars towards the house, which was almost hidden by trees. The morbid crowd made way for the two officers and speculated on their mission. The general impression was that they were the representatives of a fashionable firm of undertakers and had come to measure the victim for his coffin. Inside the grounds the Scotland Yard officers encountered a police-constable who was on guard for the purpose of preventing inquisitive strangers penetrating to the house.

"Well, Flack," said Inspector Chippenfield in a tone in which geniality was slightly blended with official superiority. "How are you to-day?"

"I'm very well indeed, sir," replied the police-constable. He knew that the state of his health was not a matter of deep concern to the inspector, but such is the vanity of human nature that he was pleased at the inquiry. The fact that there was a murdered man in the house gave mournful emphasis to the transience of human life, and made Police-Constable Flack feel a glow of satisfaction in being very well indeed.

Inspector Chippenfield hesitated a moment as if in deep thought. The object of his hesitation was to give Flack an opportunity of imparting any information that had come to him while on guard. The inspector believed in encouraging people to impart information but regarded it as subversive of the respect due to him to appear to be in need of any. As Flack made no attempt to carry the conversation beyond the state of his health, Inspector Chippenfield came to the conclusion that he was an extremely dull policeman. He introduced Flack to Detective Rolfe and explained to the latter:

"Flack was on duty on the night of the murder but heard no shots. Probably he was a mile or so away. But in a way he discovered the crime. Didn't you, Flack? When we rang up Seldon he came up here and brought Flack with him. He'll be only too glad to tell you anything you want to know."

Rolfe took an official notebook from a breast pocket and proceeded to question the police-constable. The inspector made his way upstairs to the room in which the crime had been committed, for it was his system to seek inspiration in the scene of a crime.

Tanton Gardens, a short private street terminating in a cul-de-sac, was in a remote part of Hampstead. The daylight appearance of the street betokened wealth and exclusiveness. The roadway which ran between its broad white-gravelled footwalks was smoothly asphalted for motor tyres; the avenues of great chestnut trees which flanked the footpaths served the dual purpose of affording shade in summer and screening the houses of Tanton Gardens from view. But after nightfall Tanton Gardens was a lonely and gloomy place, lighted only by one lamp, which stood in the high road more to mark the entrance to the street than as a guide to traffic along it, for its rays barely penetrated beyond the first pair of chestnut trees.

The houses in Tanton Gardens were in keeping with the street: they indicated wealth and comfort. They were of solid exterior, of a size that suggested a fine roominess, and each house stood in its own grounds. Riversbrook was the last house at the blind end of the street, and its east windows looked out on a wood which sloped down to a valley, the street having originally been an incursion into a large private estate, of which the wood alone remained. On the other side a tangled nutwood coppice separated the judge's residence from its nearest neighbours, so the house was completely isolated. It stood well back in about four acres of ground, and only a glimpse of it could be seen from the street front because of a small plantation of ornamental trees, which grew in front of the house and hid it almost completely from view. When the carriage drive which wound through the plantation had been passed the house burst abruptly into view—a big, rambling building of uncompromising ugliness. Its architecture was remarkable. The impression which it conveyed was that the original builder had been prevented by lack of money from carrying out his original intention of erecting a fine symmetrical house. The first story was well enough—an imposing, massive, colonnaded front in the Greek style, with marble pillars supporting the entrance. But the two stories surmounting this failed lamentably to carry on the pretentious design. Viewed from the front, they looked as though the builder, after erecting the first story, had found himself in pecuniary straits, but, determined to finish his house somehow, had built two smaller stories on the solid edifice of the first. For the two second stories were not flush with the front of the house, but reared themselves from several feet behind, so that the occupants of the bedrooms on the first story could have used the intervening space as a balcony. Viewed from the rear, the architectural imperfections of the upper part of the house were in even stronger contrast with the ornamental first story. Apparently the impecunious builder, by the time he had reached the rear, had completely run out of funds, for on the third floor he had failed altogether to build in one small room, and had left the unfinished brickwork unplastered.

The large open space between the house and the fir plantation had once been laid out as an Italian garden at the cost of much time and money, but Sir Horace Fewbanks had lacked the taste or money to keep it up, and had allowed it to become a luxuriant wilderness, though the sloping parterres and the centre flowerbeds still retained traces of their former beauty. The small lake in the centre, spanned by a rustic hand-bridge, was still inhabited by a few specimens of the carp family—sole survivors of the numerous gold-fish with which the original designer of the garden had stocked the lake.

Sir Horace Fewbanks had rented Riversbrook as a town house for some years before his death, having acquired the lease cheaply from the previous possessor, a retired Indian civil servant, who had taken a dislike to the place because his wife had gone insane within its walls. Sir Horace had lived much in the house alone, though each London season his daughter spent a few weeks with him in order to preside over the few Society functions that her father felt it due to his position to give, and which generally took the form of solemn dinners to which he invited some of his brother judges, a few eminent barristers, a few political friends, and their wives. But rumour had whispered that the judge and his daughter had not got on too well together—that Miss Fewbanks was a strange girl who did not care for Society or the Society functions which most girls of her age would have delighted in, but preferred to spend her time on her father's country estate, taking an interest in the villagers or walking the country-side with half a dozen dogs at her heels.

Rumour had not spared the dead judge's name. It was said of him that he was fond of ladies' society, and especially of ladies belonging to a type which he could not ask his daughter to meet; that he used to go out motoring, driving himself, after other people were in bed; and that strange scenes had taken place at Riversbrook. Flack had told his wife on several occasions that he had heard sounds of wild laughter and rowdy singing coming from Riversbrook as he passed along the street on his beat in the small hours of the morning. Several times in the early dawn Flack had seen two or three ladies in evening dress come down the carriage drive and enter a taxi-cab which had been summoned by telephone.