He at once saw the excuse: it was madness. She was mad. The sister of Altenheim and Isilda, the daughter of the last of the Malreichs, of the demented mother, of the drunken father, was herself mad. A strange madwoman, mad with every appearance of sanity, but mad nevertheless, unbalanced, brain-sick, unnatural, truly monstrous.

That he most certainly understood! It was homicidal madness. Under the obsession of an object toward which she was drawn automatically, she killed, thirsting for blood, unconsciously, infernally.

She killed because she wanted something, she killed in self-defence, she killed because she had killed before. But she killed also and especially for the sake of killing. Murder satisfied sudden and irresistible appetites that arose in her. At certain seconds in her life, in certain circumstances, face to face with this or that being who had suddenly become the foe, her arm had to strike.

And she struck, drunk with rage, ferociously, frenziedly.

A strange madwoman, not answerable for her murders, and yet so lucid in her blindness, so logical in her mental derangement, so intelligent in her absurdity! What skill, what perseverance, what cunning contrivances, at once abominable and admirable!

And Lupin, in a rapid view, with prodigious keenness of outlook, saw the long array of bloodthirsty adventures and guessed the mysterious paths which Dolores had pursued.

He saw her obsessed and possessed by her husband's scheme, a scheme which she evidently understood only in part. He saw her, on her side, looking for that same Pierre Leduc whom her husband was seeking, looking for him in order to marry him and to return, as queen, to that little realm of Veldenz from which her parents had been ignominiously driven.

And he saw her at the Palace Hotel, in the room of her brother, Altenheim, at the time when she was supposed to be at Monte Carlo. He saw her, for days together, spying upon her husband, creeping along the walls, one with the darkness, undistinguishable and unseen in her shadowy disguise.

And, one night, she found Mr. Kesselbach fastened up ... and she stabbed him.

And, in the morning, when on the point of being denounced by the floor-waiter ... she stabbed him.

And, an hour later, when on the point of being denounced by Chapman, she dragged him to her brother's room ... and stabbed him.

All this pitilessly, savagely, with diabolical skill.

And, with the same skill, she communicated by telephone with her two maids, Gertrude and Suzanne, both of whom had arrived from Monte Carlo, where one of them had enacted the part of her mistress. And Dolores, resuming her feminine attire, discarding the fair wig that altered her appearance beyond recognition, went down to the ground-floor, joined Gertrude at the moment when the maid entered the hotel and pretended herself to have just arrived, all ignorant of the tragedy that awaited her.

An incomparable actress, she played the part of the wife whose life is shattered. Every one pitied her. Every one wept for her. Who could have suspected her?

And then came the war with him, Lupin, that barbarous contest, that unparalleled contest which she waged, by turns, against M. Lenormand and Prince Sernine, spending her days stretched on her sofa, ill and fainting, but her nights on foot, scouring the roads indefatigable and terrible.

And the diabolical contrivances: Gertrude and Suzanne, frightened and subdued accomplices, both of them serving her as emissaries, disguising themselves to represent her, perhaps, as on the day when old Steinweg was carried off by Baron Altenheim, in the middle of the Palais de Justice.

And the series of murders: Gourel drowned; Altenheim, her brother, stabbed. Oh, the implacable struggle in the underground passages of the Villa des Glycines, the invisible work performed by the monster in the dark: how clear it all appeared to-day!

And it was she who tore off his mask as Prince Sernine, she who betrayed him to the police, she who sent him to prison, she who thwarted all his plans, spending her millions to win the battle.

And then events followed faster: Suzanne and Gertrude disappeared, dead, no doubt! Steinweg, assassinated! Isilda, the sister, assassinated!

"Oh, the ignominy, the horror of it!" stammered Lupin, with a start of revulsion and hatred.

He execrated her, the abominable creature. He would have liked to crush her, to destroy her. And it was a stupefying sight, those two beings, clinging to each other, lying motionless in the pale dawn that began to mingle with the shades of the night.

"Dolores... . Dolores... ." he muttered, in despair.

He leapt back, terror-stricken, wild-eyed. What was it? What was that?

What was that hideous feeling of cold which froze his hands?

"Octave! Octave?" he shouted, forgetting that the chauffeur was not there.

Help, he needed help, some one to reassure him and assist him. He shivered with fright. Oh, that coldness, that coldness of death which he had felt! Was it possible? ... Then, during those few tragic minutes, with his clenched fingers, he had... .

Violently, he forced himself to look. Dolores did not stir.

He flung himself on his knees and drew her to him.

She was dead.

He remained for some seconds a prey to a sort of numbness in which his grief seemed to be swallowed up. He no longer suffered. He no longer felt rage nor hatred nor emotion of any kind ... nothing but a stupid prostration, the sensation of a man who has received a blow with a club and who does not know if he is still alive, if he is thinking, or if he is the sport of a nightmare.

Nevertheless, it seemed to him that an act of justice had taken place, and it did not for a second occur to him that it was he who had taken life. No, it was not he. It was outside him and his will. It was destiny, inexorable destiny that had accomplished the work of equity by slaying the noxious beast.

Outside, the birds were singing. Life was recommencing under the old trees, which the spring was preparing to bring into bud. And Lupin, waking from his torpor, felt gradually welling up within him an indefinable and ridiculous compassion for the wretched woman, odious, certainly, abject and twenty times criminal, but so young still and now ... dead.

And he thought of the tortures which she must have undergone in her lucid moments, when reason returned to the unspeakable madwoman and brought the sinister vision of her deeds.

"Protect me... . I am so unhappy!" she used to beg.

It was against herself that she asked to be protected, against her wild-beast instincts, against the monster that dwelt within her and forced her to kill, always to kill.

"Always?" Lupin asked himself.

And he remembered the night, two days since, when, standing over him, with her dagger raised against the enemy who had been harassing her for months, against the indefatigable enemy who had run her to earth after each of her crimes, he remembered that, on that night, she had not killed. And yet it would have been easy: the enemy lay lifeless and powerless. One blow and the implacable struggle was over. No, she had not killed, she too had given way to feelings stronger than her own cruelty, to mysterious feelings of pity, of sympathy, of admiration for the man who had so often mastered her.

No, she had not killed, that time. And now, by a really terrifying vicissitude of fate, it was he who had killed her.

"I have taken life!" he thought, shuddering from head to foot. "These hands have killed a living being; and that creature is Dolores! ...

Dolores! ... Dolores! ..."

He never ceased repeating her name, her name of sorrow, and he never ceased staring at her, a sad, lifeless thing, harmless now, a poor hunk of flesh, with no more consciousness than a little heap of withered leaves or a little dead bird by the roadside.

Oh! how could he do other than quiver with compassion, seeing that of those two, face to face, he was the murderer, and she, who was no more, the victim?

"Dolores! ... Dolores! ... Dolores! ..."

The daylight found Lupin seated beside the dead woman, remembering and thinking, while his lips, from time to time, uttered the disconsolate syllables:

"Dolores! ... Dolores! ..."

He had to act, however, and, in the disorder of his ideas, he did not know how to act nor with what act to begin:

"I must close her eyes first," he said.

The eyes, all empty, filled only with death, those beautiful gold-spangled eyes, had still the melancholy softness that gave them their charm. Was it possible that those eyes were the eyes of a monster?

In spite of himself and in the face of the implacable reality, Lupin was not yet able to blend into one single being those two creatures whose images remained so distinct at the back of his brain.

He stooped swiftly, lowered the long, silky eyelids, and covered the poor distorted face with a veil.