"He is climbing the trellis," whispered Gourel.

"Is it high?"

"Six feet or so."

The creaking became more distinct.

"Go, Gourel," muttered M. Lenormand, "find the Doudevilles, bring them back to the foot of the wall and bar the road to any one who tries to get down this way."

Gourel went. At the same moment, a head appeared at the level of the window. Then a leg was flung over the balcony. M. Lenormand distinguished a slenderly-built man, below the middle height, dressed in dark colours and without a hat.

The man turned and, leaning over the balcony, looked for a few seconds into space, as though to make sure that no danger threatened him. Then he stooped down and lay at full length on the floor. He appeared motionless. But soon M. Lenormand realized that the still blacker shadow which he formed against the surrounding darkness was coming forward, nearer.

It reached the bed.

M. Lenormand had an impression that he could hear the man's breathing and, at the same time, that he could just see his eyes, keen, glittering eyes, which pierced the darkness like shafts of fire and which themselves could see through that same darkness.

Pierre Leduc gave a deep sigh and turned over.

A fresh silence... .

The man had glided along the bed with imperceptible movements and his dark outline now stood out against the whiteness of the sheets that hung down to the floor.

M. Lenormand could have touched him by putting out his arm. This time, he clearly distinguished the breathing, which alternated with that of the sleeper, and he had the illusion that he also heard the sound of a heart beating.

Suddenly, a flash of light... . The man had pressed the spring of an electric lantern; and Pierre Leduc was lit full in the face, but the man remained in the shade, so that M. Lenormand was unable to see his features.

All that he saw was something that shone in the bright space; and he shuddered. It was the blade of a knife; and that thin, tapering knife, more like a stiletto than a dagger, seemed to him identical with the weapon which he had picked up by the body of Chapman, Mr. Kesselbach's secretary.

He put forth all his will-power to restrain himself from springing upon the man. He wanted first to know what the man had come to do.

The hand was raised. Was he going to strike? M. Lenormand calculated the distance in order to stop the blow... . But no, it was not a murderous gesture, but one of caution. The hand would only fall if Pierre Leduc stirred or tried to call out. And the man bent over the sleeper, as though he were examining something.

"The right cheek," thought M. Lenormand, "the scar on the right cheek.

... He wants to make sure that it is really Pierre Leduc."

The man had turned a little to one side, so that only his shoulders were visible. But his clothes, his overcoat, were so near that they brushed against the curtains behind which M. Lenormand was hiding.

"One movement on his part," thought the chief detective, "a thrill of alarm; and I shall collar him."

But the man, entirely absorbed in his examination, did not stir. At last, after shifting the dagger to the hand that held the lantern, he raised the sheet, at first hardly at all, then a little more, then more still, until the sleeper's left arm was uncovered and the hand laid bare. The flash of the lantern shone upon the hand. The fingers lay outspread. The little finger was cut on the second joint.

Again Pierre Leduc made a movement. The light was immediately put out; and, for an instant, the man remained beside the bed, motionless, standing straight up. Would he make up his mind to strike? M. Lenormand underwent the agony of the crime which he could so easily prevent, but which he did not want to forestall before the very last second.

A long, a very long silence. Suddenly, he saw or rather fancied that he saw an arm uplifted. Instinctively he moved, stretching his hand above the sleeper. In making this gesture, he hit against the man.

A dull cry. The fellow struck out at space, defended himself at random and fled toward the window. But M. Lenormand had leapt upon him and had his two arms around the man's shoulders.

He at once felt him yielding and, as the weaker of the two, powerless in Lenormand's hands, trying to avoid the struggle and to slip from between his arms. Lenormand, exerting all his strength, held him flat against his chest, bent him in two and stretched him on his back on the floor.

"Ah, I've got him, I've got him!" he muttered triumphantly.

And he felt a singular elation at imprisoning that terrifying criminal, that unspeakable monster, in his irresistible grip. He felt him living and quivering, enraged and desperate, their two lives mingled, their breaths blended:

"Who are you?" he asked. "Who are you? ... You'll have to speak.

And he clasped the enemy's body with still greater force, for he had an impression that that body was diminishing between his arms, that it was vanishing. He gripped harder ... and harder... .

And suddenly he shuddered from head to foot. He had felt, he still felt a tiny prick in the throat... . In his exasperation, he gripped harder yet: the pain increased! And he observed that the man had succeeded in twisting one arm round, slipping his hand to his chest and holding the dagger on end. The arm, it was true, was incapable of motion; but the closer M. Lenormand tightened his grip, the deeper did the point of the dagger enter the proffered flesh.

He flung back his head a little to escape the point: the point followed the movement and the wound widened.

Then he moved no more, remembering the three crimes and all the alarming, atrocious and prophetic things represented by that same little steel needle which was piercing his skin and which, in its turn, was implacably penetrating... .

Suddenly, he let go and gave a leap backwards. Then, at once, he tried to resume the offensive. It was too late. The man flung his legs across the window-sill and jumped.

"Look out, Gourel!" he cried, knowing that Gourel was there, ready to catch the fugitive.

He leant out. A crunching of pebbles ... a shadow between two trees, the slam of the gate... . And no other sound ... no interference.

Without giving a thought to Pierre Leduc, he called:

"Gourel! ... Doudeville!"

No answer. The great silence of the countryside at night... .

In spite of himself, he continued to think of the treble murder, the steel dagger. But no, it was impossible, the man had not had time, had not even had the need to strike, as he had found the road clear.

M. Lenormand jumped out in his turn and, switching on his lantern, recognized Gourel lying on the ground:

"Damn it!" he swore. "If they've killed him, they'll have to pay dearly for it."

But Gourel was not dead, only stunned; and, a few minutes later, he came to himself and growled:

"Only a blow of the fist, chief ... just a blow of the fist which caught me full in the chest. But what a fellow!"

"There were two of them then?"

"Yes, a little one, who went up, and another, who took me unawares while I was watching."

"And the Doudevilles?"

"Haven't seen them."

One of them, Jacques, was found near the gate, bleeding from a punch in the jaw; the other a little farther, gasping for breath from a blow full on the chest.

"What is it? What happened?" asked M. Lenormand.