There are no cardboard castles, kilts or sporrans in director John Doyle and designer Liz Ascroft’s Scotland.

Their setting for Opera Australia’s new production of Donizetti’s Lucia di Lammermoor (in partnership with Houston Grand Opera and Teatro La Fenice) is all clouds and severity, ordered in spare symmetrical patterns that isolate the chief protagonists and exclude their messy emotions.

Into that dour world steps Jessica Pratt as Lucia who sang her first Cavatina in Act 1 in smooth, even notes, each tone a pearl on an ordered necklace, breaking only at the cadence into expressiveness and, later, overflowing into immaculate trills.

By the famous mad-scene of Act III all order has gone, Pratt soaring with unfettered fluidity across full vocal range, throwing out loosely related musical phrases, her tone matching the pure flute sound as though it were the cold moon that had driven her insane.

Pratt’s performance was a tour-de-force of vocal polish, broaching stratospheric heights with never a hint of harshness or strain. Tenor Michael Fabiano’s trajectory as her ill-fated lover Edgardo follows a different path, marching into his Act 1 duet with Lucia with splendidly blooming radiance and fearless ease. At the end his projection retains courageous vocal swagger, but the defeated spirit is reduced to a final melodramatic spasm before Scotland’s portentous clouds. These two make up a magnificent principle couple but are only the crest of a strong and even cast.

Giorgio Caoduro as Lucia’s brother and betrayer, Enrico, began with a forceful edge of rasping insistence, maintaining implacable firmness throughout. By way of contrast, the compromised humanity of the chaplain Raimondo was captured in the warm complexity of Richard Anderson’s soft-edged tone like velvet turning stiff as it ages.

Jane Ede, as the maid Alisa, found a sound that matched and followed Pratt’s in pastel tones, complementing, questioning and balancing. Although the most impactful entrance of the ill-fated husband Arturo is as the bloodstain on Lucia’s nightie, John Longmuir sang with appropriately clean cut lines, while Benjamin Rasheed as the spy who comes in from the cold Scottish highlands had keen focus.

Like so much bel-canto opera, there are large swaths where action has to be put aside while soloists and chorus stand and sing. Doyle made a virtue rather than an awkwardness of this, arranging the chorus in diagonals and horizontals whose geometry was picked up in the abstract shapes of Ascroft’s set.

For the great sextet of Act II, Chie mi frena in tal mome, lighting designer Jane Cox picked out pools across the stage to isolate each character in thought. From their neat patterns the chorus sang with forceful splendour and moulded balance.

Conductor Carlo Montanaro maintained a sense of dramatic momentum injecting urgency and excitement strategically without rushing, and drawing unforced colour from the orchestra.

This is a production where musical feeling symbolically fights the societal straitjacket, and although the latter wins it is the irrationality of musical seduction that endures.