"Lucia di Lammermoor" is generally held to be Donizetti's finest work. "In it the vein of melody—now sparkling, now sentimental, now tragic—which embodies Donizetti's best claim on originality and immortality, finds, perhaps, freest and broadest development." These words are quoted from Baker's Biographical Dictionary of Musicians, a volume that rarely pauses to comment on an individual work. "Lucia" is indeed its composer's masterpiece; and a masterpiece of Italian opera in the older definition of that term. Its melodies are many and beautiful, and even when ornate in passages, are basically expressive of the part of the tragic story to which they relate. Moreover, the sextet at the end of the second act when Edgar of Ravenswood appears upon the scene just as Lucy with trembling hand has affixed her signature to the contract of marriage between Lord Bucklaw and herself, ranks as one of the finest pieces of dramatic music in all opera, and as a concerted number is rivalled, in Italian opera, by only one other composition, the quartet in "Rigoletto."

The sextet in "Lucia" rises to the full height of the dramatic situation that has been created. It does so because the music reflects the part each character plays in the action. It has "physiognomy"—individual aspect and phraseology for each participant in the drama; but, withal, an interdependence, which blends the voices, as they are swept along, into one grand, powerful, and dramatic climax.

Another number, the mad scene in the third act, gives coloratura sopranos an opportunity for technical display equal to that afforded by the lesson scene in "Il Barbiere di Siviglia"; and, unlike the latter, the music does not consist of interpolated selections, but of a complete scena with effective recitatives and brilliant solos, that belong to the score.

In the story of "Lucia," the heroine's brother, Lord Henry Ashton of Lammermoor, in order to retrieve his fallen fortunes, and extricate himself from a perilous situation in which his participation in political movements directed against the King has placed him, arranges a marriage between his sister and Lord Arthur Bucklaw. Lucy herself knows nothing of this arrangement. Henry, on the other hand, is equally ignorant of an attachment which exists between Lucy and Edgar of Ravenswood, between whose family and his own there long has been a deadly feud. When he discovers it, he uses the most underhand methods to break it off.

Edgar of Ravenswood is the last of his race. While he is absent on a mission to France in the interests of Scotland, he despatches many letters to Lucy. These letters are intercepted by Henry who also arranges that a forged paper, tending to prove the infidelity of Edgar, is shown to Lucy. Urged by the necessities of her brother, and believing herself deserted by her lover, Lucy unwillingly consents to become the bride of Lord Arthur Bucklaw. But, just as she has signed the marriage contract, Edgar of Ravenswood suddenly appears. He has returned from France, and now comes to claim the hand of Lucy—but too late. Convinced that Lucy has betrayed his love, he casts the ring she gave him at her feet and invokes imprecations upon her and his ancient enemies, the House of Lammermoor.

At night he is sought out in his gloomy castle by Henry. They agree upon a duel to be fought near the tombs of the Ravenswoods, on the ensuing morning, when Edgar, weary of life, and the last of a doomed race, intends to throw himself on his adversary's weapon. But the burden of woe has proved too much for Lucy to bear. At night, after retiring, she goes out of her mind, slays her husband, and dies of her sorrows.

Edgar awaits his enemy in the churchyard of Ravenswood. But Ashton has fled. Instead, Edgar's solitude is interrupted by a train of mourners coming from the Castle of Lammermoor. Upon hearing of Lucy's death he plunges his dagger into his breast, and sinks down lifeless in the churchyard where repose the remains of his ancestors.

On the stage this story is developed so that shortly after the curtain rises on Act I, showing a grove near the Castle of Lammermoor, Henry learns from Norman the latter's suspicions that Lucy and Edgar have been meeting secretly in the park of Lammermoor. Norman has despatched his huntsmen to discover, if they can, whether or not his suspicions are correct. "Cruda funesta smania" (each nerve with fury trembleth) sings Henry.

Returning, the hunters relate, in a brisk chorus, that

Long they wander'd o'er the mountain,
Search'd each cleft around the fountain,