Thompson nodded his head comprehendingly.

"Make it clear that they are there to watch; but I doubt if they'll see anything," he added.

II

At eleven o'clock on the night of July the 23rd, two motor lorries glided slowly along some three miles distant from one another. From their interiors silent forms dropped noiselessly on to the moon-white road. A moment later, slipping into the shadow of the hedge, they disappeared. All the previous night men had watched and waited; but nothing had happened. Now they were to try again.

Overhead the moon was climbing the sky, struggling against ma.s.ses of cloud that from time to time swung themselves across her disc.

In the village of Hempdon all was quiet. The last light had been extinguished, the last dog had sent forth a final challenging bark, hoping that some neighbouring rival would answer and justify a volume of canine protest.

On the western side of the highway, and well behind the houses, two figures were standing in the shadow cast by a large oak. Their faces and hands were blackened, rendering them indistinguishable from their surroundings.

One wore a shade over a pair of gold-rimmed spectacles, a precaution against the moonlight being reflected on the lenses.

Half an hour, an hour, an hour and a half pa.s.sed. They waited.

Presently one gripped the arm of the other and pointed. At the back of the house immediately-opposite there was a slight movement in the shade cast by a hedge. Then the line readjusted itself and the shadow vanished. A moment later it reappeared in a patch of moonlight, looking like a large dog.

Stooping low Malcolm Sage and Thompson followed the dog-like form, themselves taking advantage of every patch of shadow and cover that offered.

The mysterious form moved along deliberately and without haste, now disappearing in the shadow cast by some tree or bush, now reappearing once more on the other side.

It was obviously taking advantage of everything that tended to conceal its movements.

Once it disappeared altogether, and for five minutes the two trackers lay on their faces and waited.

"Making sure he's not being followed," whispered Thompson, and Malcolm Sage nodded.

Presently the figure appeared once more and, as if rea.s.sured, continued its slow and deliberate way.

Once a dog barked, a short, sharp bark of uncertainty. Again there was no sign of the figure for some minutes. Then it moved out from the surrounding shadows and continued its stealthy progress.

Having reached the outskirts of the village, it continued its crouching course along the western side of the hedge flanking the roadside.

Malcolm Sage and Thompson followed under the shadow of a hedge running parallel.

For a mile the slow and laborious tracking continued. Suddenly Malcolm Sage stopped. In the field on their right two horses were grazing in the moonlight. It was the scene of the tragedy of the month previous!

For some minutes they waited expectantly. Suddenly Malcolm Sage gripped Thompson's arm and pointed. From under the hedge a dark patch was moving slowely towards the nearer of the two animals. It was apparently the form of a man, face downward, wriggling along inch by inch without bending a limb.

"Get across. Cut off his retreat," whispered Sage. "Look out for the knife."

Thompson nodded and slid away under cover of the hedge separating the field in which the horses were from that along which the watchers had just pa.s.sed.

Slowly the form approached its quarry. Once the horse lifted its head as though scenting danger; but the figure was approaching upwind.

Suddenly it raised itself, appearing once more like a large dog.

Then with a swift, panther-like movement it momentarily disappeared in the shadow cast by the horse.

There was a m.u.f.fled scream and a gurgle, as the animal collapsed, then silence.

A minute later the form seemed to detach itself from the carcase and wriggled along towards the hedge, a dark patch upon the gra.s.s.

Malcolm Sage was already half-way through the second field, keeping well under the shelter of the hedge. He reached a spot where the intersecting hedge joined that running parallel with the highroad.

There was a hole sufficiently large for a man to crawl through from one field to the other. By this Malcolm Sage waited, a life-preserver in his hand.

At the sound of the snapping of a twig, he gripped his weapon; a moment later a round, dark shape appeared through the hole in the hedge. Without hesitating Malcolm Sage struck.

There was a sound, half grunt, half sob, and Malcolm Sage was on his feet gazing down at the strangest creature he had ever encountered.

Clothed in green, its face and hands smeared with some pigment of the same colour, lay the figure of a tall man. Round the waist was a belt from which was suspended in its case a Gurkha's kukri.

Malcolm Sage bent down to unbuckle the belt. He turned the man on his back. As he did so he saw that in his hand was a small, collapsible tin cup covered with blood, which also stained his lips and chin, and dripped from his hands, whilst the front of his clothing was stained in dark patches.

"I wonder who he is," muttered Thompson, as he gazed down at the strange figure.

"Locally he is known as the Rev. Geoffrey Callice," remarked Malcolm Sage quietly.

And Thompson whistled.

III

"And that d.a.m.ned scoundrel has been fooling us for two years." Sir John Hackblock glared at Inspector Wensdale as if it were he who was responsible for the deception.

They were seated smoking in Sir John's library after a particularly early breakfast.

"I always said it was the work of a madman," said the inspector in self-defence.

"Callice is no more mad than I am," snapped Sir John. "I wish I were going to try him," he added grimly. "The scoundrel! To think----"

His indignation choked him.

"He is not mad in the accepted sense," said Malcolm Sage as he sucked meditatively at his pipe. "I should say that it is a case of race-memory."

"Race-memory! Dammit! what's that?" Sir John Hackblock snapped out the words in his best parade-ground manner. He was more purple than ever about the jowl, and it was obvious that he was prepared to disagree with everyone and everything. As Lady Hackblock and her domestics would have recognised without difficulty, Sir John was angry.

"How the devil did you spot the brute?" he demanded, as Malcolm Sage did not reply immediately.

"Race-memory," he remarked, ignoring the question, "is to man what instinct is to animals; it defies a.n.a.lysis or explanation."

Sir John stared; but it was Inspector Wensdale who spoke.