In a certain pretty village in Italy, the light-hearted peasants were gathered together one summer evening on the shady green, talking in groups as they waited to witness the betrothal of Elvino, a prosperous young farmer, and his fair sweetheart, Amina, whose nuptials were to be celebrated on the morrow. The wreaths and garlands of flowers for the wedding decorations were being merrily set up by willing hands, and the village already wore a gala air; for all were looking forward eagerly to the coming festivities, with the exception of one person, who alone refused to be joyful.

This was Lisa, the pretty young hostess of the village inn, who having once received attentions herself from the handsome Elvino, had felt slighted when he fixed his affections upon Amina, whose beauty and sweet winning ways had made her the belle of the village; and now, as she mingled with the merry throng on the green, she was filled with envy for the happy fate of the bride-elect, and could do nothing but make spiteful remarks about her rival, declaring her to be a mere nobody, and not worthy of so great a piece of fortune.

For Amina was but a poor orphan, who had been brought up by Dame Teresa of the Mill, a worthy woman who had loved and cared for her as though she were her own child; but in spite of her unknown birth and dependent position, Amina was beloved by all the villagers, whose hearts she had won by her many deeds of kindness. But Lisa's jealousy would not allow her to see any perfection in the gentle Amina; and so full of envy and disappointment did she feel just now that to all the remarks made to her by her devoted admirer, Alessio, she only returned snappish replies, which, however, disconcerted her swain but little. For Alessio was a merry, lively fellow, full of fun, and not easily discouraged; and having conceived a great admiration for the pretty but sharp-tongued Lisa, he was for ever coaxing her to marry him, and in spite of her many snubs, still felt confident of success in the end.

As they walked about the green this evening, he said again; "Come, Lisa, let us also sign our marriage contract whilst the Notary is here, and save him the trouble of coming again!"

But to this cool suggestion, however, Mistress Lisa merely tossed her head, and turned impatiently away; and Alessio, nothing daunted, began to join heartily in the merry wedding song he had himself composed in honour of the day, which the villagers had just raised as the pretty Amina appeared on the green, accompanied by Dame Teresa.

When the song came to an end Amina thanked her friends in a gentle voice for their kindly wishes; and then, turning to Alessio and Lisa, she mischievously suggested that they should follow her example and plight their troth with her that night.

"'Tis just what I have been saying!" cried the irrepressible Alessio, gleefully. "Come, Lisa, say that you will, for I feel I must get married to-day, and if you won't have me, I'll have to marry Dame Teresa!"

All laughed merrily at this; but Lisa sulkily refused to join in the fun, for Elvino had now arrived, and the sight of his devoted attentions to Amina caused her jealousy and disappointment to smart afresh. The Notary having also now arrived with the marriage contract, the guests gathered around a table which had been placed beneath the trees outside Dame Teresa's house; and Elvino and Amina, having signed their names to the paper, their betrothal was thus formally concluded.

Just as the happy pair were receiving the congratulations of their friends, a strange cavalier—whose gay attire, aristocratic bearing, and deferential attendants proclaimed him to be a person of rank—approached the inn, and inquired of the bystanders if the landlord's chÂteau was near at hand; and on being informed that it was some little distance away, he announced his intention of passing the night at the inn.

On hearing this, Lisa, mindful of her duties as hostess, hurried forward officiously, and offered her best accommodation to the stranger; and then, having received some gallant compliments from her guest, who had an appreciative eye for a pretty face, she hastened within doors to make all ready, beaming with pleasure.

The stranger was, however, more greatly struck with the beauty of Amina, to whom he next addressed himself, declaring that she reminded him of someone whom he had long since loved and lost; and so intense was his gaze, that after he had departed within the inn, Elvino, seized with a sudden pang of jealousy, reproached the maiden for having thus spoken with the newcomer. But Amina tenderly reassured her anxious lover, declaring that she loved but him alone; and the little cloud that had threatened to gather, now quickly vanished.

As they moved away happily together, Alessio presently came running out to announce that he had discovered the stranger to be none other than the Count Rodolpho, their own Lord of the Soil, whose chÂteau overlooked the village, and who had not visited his native place since he was a child; and upon hearing this interesting news, the villagers were all filled with great excitement, and, as they trooped away to their homes arranged to proceed to the inn at break of day to sing a song of welcome to their Seigneur, and to show their joy at his arrival.

Some hours later, Count Rodolpho was conducted to the finest chamber which the old-fashioned inn afforded, and which, though it had the reputation of being haunted, he had laughingly insisted upon occupying, finding it quaint and comfortable; and before retiring for the night, though it was already late, Lisa appeared at the door, to ask if all his wishes had been attended to, and also to offer her respects to him as her Seigneur.

The Count, being a gay cavalier, and accustomed to making conquests wherever he went, invited her to enter, thinking that a flirtation with his pretty hostess would pass the time pleasantly; and Lisa, nothing loath, but delighted at the impression she imagined she had made on her guest, was willing enough to accept his attentions. The Count's pretty speeches pleased her very well, nor did she object when he snatched a kiss or two; but, not daring to remain longer, since the night was advancing, she was just about to depart, when a strange interruption came. Just at that moment, a slight female figure, clad in a long white robe, softly entered the room, and walked slowly across the floor, speaking aloud, as though holding a conversation with some unseen person; and to the great amazement of the Count and Lisa, they saw that this mysterious nocturnal visitor was Amina, who, although her eyes were wide open, saw them not, since she was walking in her sleep. For, though unknown to anyone, and still less to herself, Amina was a somnambulist, and had quite unconsciously walked from her own home and entered through the unfastened door of the inn; and as Count Rodolpho now gazed in astonishment upon the maiden, whose lovely face had so interested him earlier in the evening, he was filled with a strange, deep emotion, and listened eagerly to the words she said, from which he gathered that she imagined herself speaking to Elvino, since she spoke reproachfully of his having for a moment doubted her faithful heart.

But Lisa, though at first alarmed, quickly saw in this unforeseen circumstance, a means for satisfying her petty spite against the orphan she despised; and, quickly making her escape from the room, she determined to seek out Elvino, and prove to him that his betrothed was base and unfaithful to him, since she had found her in the chamber of the Count Rodolpho.

Meanwhile, Amina continued to speak in tender accents of her love for Elvino; and, unconsciously taking the Count's hand in hers, she softly caressed it, repeatedly avowing her passion.

Count Rodolpho watched the sleeping maiden with increasing emotion, feeling the charm of her ethereal beauty creeping over him like a spell; and at last, fearful of awakening her, and not daring to trust himself longer in her sweet presence, since, though her helplessness appealed to his chivalry, he felt drawn towards her by a strange attraction, he hastily left the room, and, leaving the inn at once, made his way to his own chÂteau.

After he had gone, Amina ceased to speak; and, presently sinking upon a couch, remained there in peaceful slumber.

It was now day-break; and the peasants, in accordance with the arrangement of the evening before, assembled in the inn, and, making their way to the Count's chamber, began to sing a joyous song of welcome, which they hoped would presently arouse him from his slumbers. Soon afterwards, Lisa entered the room with Elvino, whom she had brought to behold for himself his betrothed slumbering in the chamber of the stranger, cruelly and unjustly keeping from him the fact that Amina had walked there in her sleep.

Elvino, who had indignantly refused to believe her story, now uttered an exclamation of grief and despair on beholding what appeared to him the proof of Lisa's statement; and at that moment Amina, awakened by the singing, opened her eyes, and was quickly filled with amazement on beholding her unaccustomed surroundings. As she rose from the couch in bewilderment, Elvino burst forth into angry reproaches, declaring her to be faithless and base; and in spite of poor Amina's piteous assurances of innocence, since she could not explain how she came to be found in such a compromising situation, he spurned her with scorn, and, thrusting aside her clinging arms, departed in anger.

Amina, overcome with grief and despair, sank sobbing into the arms of Dame Teresa, who, though not understanding the mystery, yet believed her to be innocent, and led her away with great tenderness; and the peasants then sadly dispersed, loath to think ill of the pretty maiden they loved so well, yet compelled to admit the evidence of their own eyes. But they were not satisfied; and later on in the day they set off to seek out Count Rodolpho in his chÂteau, and to learn what he knew of this strange matter, and if he had indeed enticed the poor girl to her ruin.

Meanwhile, Lisa was triumphant; and, having thus succeeded in bringing disgrace and ignominy upon her rival, she sought out Elvino, who had wandered into the woods near the chÂteau, and tenderly offered words of comfort to him, and by encouraging his rage against Amina, led him artfully to think of renewing his vows to herself; and then wisely refraining from becoming too importunate, she left him to his own reflections again, and wandered alone down another glade. Here she was joined by the lively Alessio, who, after first bewailing the sad fate of Amina, made the brilliant suggestion that Lisa should marry him at once, so that the wedding decorations should not be wasted, a suggestion, however, which was again disdainfully flouted by the captious Lisa, who informed him that she already felt assured of eventually securing the more prosperous Elvino as a husband. Alessio, well used to such rebuffs, and not the least disconcerted by this surprising announcement, still pressed his own claims; and then seeing that the peasants were approaching from the chÂteau, the wrangling pair set off to join them.

Meanwhile, Amina, accompanied by the sympathetic Dame Teresa, had also sought solace for her woe in the woods; and presently coming face to face with the unhappy Elvino, she once more besought him to believe in her innocence. Elvino, though filled with emotion at beholding the maiden whom he believed had wronged him, still refused, however, to listen to her pleadings, and again turning from her with scorn and anger, hurried quickly away; and as Dame Teresa vainly endeavoured to comfort the now heart-broken girl, the peasants came in sight, headed by Count Rodolpho, who, having heard from them of Amina's sad plight, had now come to prove her innocence.

Full of compassion, he approached the half-fainting girl; and, seeing that she was utterly exhausted by the strain that had been put upon her, he bade Dame Teresa to take her into a neighbouring mill, and make her rest for a while, promising that in the meantime, he would seek out Elvino and try to convince him of the innocence of his betrothed.

When Dame Teresa had led the weary Amina into the mill, the peasants went to seek Elvino; and when they had at length found and persuaded him to return with them, the Count bade him be of good comfort and cease to mourn, since Amina was still worthy of his love. He then described to him that the maiden had entered his room the night before in her sleep, explaining that she was a somnambulist, and, as such, utterly unconscious of her actions at the time; but Elvino and the simple peasants, never before having heard of this strange phenomenon, were scarcely yet convinced, finding it difficult to realize such a curious circumstance, which had not come within their experience before. But whilst they were still wondering at the story that had been told to them, they saw Amina softly approaching from the mill, passing them with wide-open, unseeing eyes, and uttering Elvino's name in loving accents; and, seeing that the maiden was again walking in her sleep, the Count explained this fact to the peasants, and bade them remain quiet until she should awaken.

Elvino, overjoyed at this final proof of his beloved one's innocence, could scarcely restrain his happy feelings, watching the lovely maiden's movements with eager interest; and when she presently awakened to full consciousness, he clasped her in his arms with joy, beseeching her to forgive him for doubting her faith.

Amina, full of happiness at thus learning that Elvino still loved her, and no longer believed her to be false, was soon restored to her accustomed gaiety; and so the reunited pair were wedded that same day ere the sun went down, amidst the great rejoicings of the villagers, who were filled with delight that the fair maiden they loved so well was now cleared from all reproach.