After twenty years of high service in the army, a gentleman of the country, Monsieur d'Heurteleure returned to settle. He married shortly after Mademoiselle Callestie, a poor girl of good family and great beauty. The wedded pair lived at the d'Heurteleure mansion. The nobles of the city frequented the house, the most assiduous in his visits being Monsieur d'Aiglieul. He had served under and was related to Monsieur d'Heurteleure, who was very fond of him. Life at the mansion was very simple, no pomp, very few domestics; the dignity of rank was upheld by the vast proportion of the apartments, the width of the stairways, and the general aspect of antiquity.
Whether they grew weary of the dull existence in this old town after the excitements of a military life, were seized suddenly by a spirit of adventure, or from whatever cause it might have come, Monsieur d'Heurteleure and Monsieur d'Aiglieul disappeared one day, no one knew whither. Time passed. The searches were fruitless. Some mystery was hinted at. Madame d'Heurteleure wept. All sorts of singular suspicions were afloat, which finally reached the court where these two gentlemen were still remembered. One day the double disappearance was mentioned in the hearing of Monsieur d'Amercœur, who determined to solve the enigma. He was empowered with full authority to act and at once he set about it.
His first care was to assume a monastic frock, certain with this attire to penetrate everywhere, through half-opened doors as well as through the fissures of conscience, and Dom Ricard helped him to the best of his power. For a while his researches were without result; but aided by the incognito of his costume and his apparent calling, his inquiries were patient and diverse. He hovered about the d'Heurteleure house, scrutinized the people and the habits, studied the life. He listened to and weighed all the still vivacious rumors. In vain. He wished to see Madame d'Heurteleure. He was told that she was ill. Every day he passed the house; following the street which rises around the sub-basement, he reached the front, pausing sometimes to slake his thirst at the fountain. Returning, as he descended the steps, he examined the enormous foundations of stone and solid rock, longing to apply his ear and listen to their mystery, for it seemed to him that the flanks of the old castle contained the fantom of the secret, which he had come to evoke from silence before it passed into oblivion. At last, discouraged, he was on the point of giving up. He would have taken leave of Dom Ricard but for the old monk's urgent advice to remain. The venerable prior enjoyed the society of this sheep, so dissimilar to the members of the flock which his wooden cross conducted in the monotonous paths of the Order.
One day toward five o'clock in the afternoon, Monsieur d'Amercœur went out by the old portal and strolled amid the tall grasses of the avenue. The moment was melancholy and grandiose; the trees threw their shadows across the funereal path, the lizards ran over the warm stones of the antique tombs and in and out of their fissures. With one hand Monsieur d'Amercœur held up the long monk's frock, with the other he held the key to open the heart-shaped lock of the medicinal garden, where he loved to wander. He wished to visit it once more before he went away, to hear once more the soles of his sandals scraping over the gravel, while his frock brushed the borders of boxwood. The symmetry of the plots pleased him; their squares contained delicate plants and curious flowers; little pools nourished aquatic specimens which plunged their roots into the water, flowered and mirrored their bloom. At the intersection of the paths stood porcelain urns painted with emblems and pharmaceutical designs, with serpents twisted about the handles, and these urns contained varieties rare and precious. Above the walls waved the tops of the poplars; from the kitchen gardens off to one side, separated by high green trellises, came the sound of a rake, the striking of a spade against a watering can, the little sound of shears clipping the young shoots; in here all was silence; a flower bent, flexible, under the weight of an insect, swallows darted about; dragon flies flitted across the greenish water; heavy plants and delicate vines twined and intertwined.
Monsieur d'Amercœur was going toward the door of this odd little enclosure when, at the end of the avenue, he saw approaching a woman dressed in black. She walked slowly with faltering steps. By some inner revelation he knew at once that this was Madame d'Heurteleure. He slackened his own pace, so as to meet her at the moment when he stopped before the door. Arrived there, he put the key into the lock. At the sound the lady started and hesitated. He stooped as though trying to turn the key. She wished to profit by this moment to pass; but found herself face to face with him as he suddenly turned. She stood with one hand pressing down her palpitating heart. He saw a face pale and lovely, though haggard from grief and insomnia, with troubled eyes, half-parted lips. Then he entered quickly, closing the door and leaving in the iron-heart of the lock the key.
The next day he was meditating in the little cloister when a messenger came to tell him that a veiled lady desired to speak with him. She was admitted. He recognized Madame d'Heurteleure, and invited her to be seated on a stone bench. The doves cooed softly on the capitals of the quiet cloister, their murmurs mingled with the sighs of the penitent. She sank on her knees, and with bent head and hands folded in his wide sleeves Monsieur d'Amercœur listened to her dolorous confession. It was a horrible and tragic story. Why relate it to him? Because her secret seemed to have been laid bare. When she saw a monk holding a key to open that heart-shaped lock, she felt as though he meant to force open her conscience. Their meeting seemed like a decree of fate, his gesture a mysterious allusion to the deliverance of her soul imprisoned in the horror of its silence.
Her marriage with Monsieur d'Heurteleure was loveless. She esteemed, while she feared his noble character, the hardness of which intimidated her confidence and discouraged her tenderness. Years passed. One winter Monsieur d'Aiglieul appeared and called frequently. He was handsome and still young. She yielded to his love. Then followed days of joy and terror; a dread of discovery and an agony of remorse. Monsieur d'Heurteleure seemed unaware of their perfidy, though he grew suddenly old and another deep line was added to those already furrowing his brow. He was as usual often absent. One evening Madame d'Heurteleure retired to her room about midnight. She felt depressed. Monsieur d'Aiglieul had not appeared and he seldom missed a day. As she was combing her hair before a mirror she saw the door open, and her husband entered. He was booted, but his boots bore no trace of outdoor mire; his coat looked dusty, a long spider web hung from his sleeve and in his hand he held a key. Without speaking he went directly to the wall of the chamber where a nail fastened an ivory crucifix, which he tore off and broke upon the floor, while in its place he suspended the heavy rusty key. Madame d'Heurteleure gazed for a moment without comprehending, then all at once her hands clasped her heart, she gave a cry and fell unconscious.
When she came to herself the whole affair was clear to her. Her husband had allured Monsieur d'Aiglieul into some trap. The old mansion in its invisible depths contained dungeons, chambers of eternal oblivion. A cry, his, vibrated still in her ears. It seemed to come from below, deafened by the piled-up stone, piercing the superposed arches, reaching her from those lips forever separated by the thickness of the walls. She tried to get out, the door was fastened, the windows were padlocked, the domestics occupied another part of the house and were beyond her call. The next day Monsieur d'Heurteleure came to bring her food. Each day he came. The spider's web still hung from his dusty sleeve, his boots creaked on the tesselated floor, the great line on his forehead deepened in a pallor of sleepless misery. He went away silently and to her tears and supplications he replied only by a brief gesture, showing the key hung against the wall.
During those tragic days the wretched woman lived with her eyes fixed on the horrible ex-voto, which grew larger to her vision, became enormous. The patches of rust looked like red blood. The house was still as death. Toward evening a step was heard. Monsieur d'Heurteleure again entered bearing a lamp and a basket. His head had grown white, he did not now so much as glance at the unhappy being who groveled at his feet, but he never failed to stare greedily at the key. Then at last Madame d'Heurteleure understood the desire which gnawed, which was devouring him—to see his rival in death, to gloat over his vengeance, to feel of the corruption that had once been flesh and blood, to take down that key he had hung on the wall in place of the Sign of Pardon, the ivory emblem of which he had shattered to substitute an iron symbol of eternal rancor. But alas! vengeance never is satisfied, always she craves for more; frenzied, insatiable, she feeds on her own vehemence to the very dregs of memory, until the end of life.
Monsieur d'Heurteleure felt that she guessed his morbid longing and that added to his torture. The adamant of his pride was streaked with veins of blood. One night when Madame d'Heurteleure slumbered, stretched on her bed, she heard her door open softly and saw her husband on the threshold. He carried a lamp with the flame turned low, and walked as lightly as a shadow without a sound, as though the sombre somnambulism of his fixed idea had made of him an imponderable fantom. He crossed the room, reached up, took down the key and went out again. There was a dead silence. A fly awakened by the light buzzed for an instant and then ceased. The door remained on the latch. Madame d'Heurteleure bounded up. In her bare feet she slipped into the hall. Her husband was going downstairs; she followed him. At the ground floor he continued to descend; the stairway plunged into gloom, but she could hear along the subterranean corridors the steps which preceded her. They were now in the ancient substructions of the castle. The walls sweated, the ceilings were vaulted. A last stairway twisted its spiral into the rock. At its base the light of the vanishing lamp still glimmered on the slimy pavement. Bending forward, Madame d'Heurteleure listened. A grating sound reached her and the light disappeared. At the foot of the stairs she found a circular chamber. An opening in the wall revealed a shallow bay; she still crept on, until, at the end of the passage, by feeling her way, she recognized a door very slightly ajar. She pushed it open. In a sort of square hole, vaulted above and tiled below, Monsieur d'Heurteleure was seated beside his little lamp. He was motionless, staring with wide-open eyes. He looked at his wife without seeing her. A nauseating odor came from the cell, and beyond the shadow spread over the tiles lay a fleshless hand already greenish in hue.