The final moment looked duff; but by then, we were moved and uplifted.To 5 July (01962 868600). Since its revival in 2002, the Isle of Wight Festival has risen from underdog of the season to mainstay. An event that has to live up to hosting Hendrix and Dylan in its original incarnation now attracts suitably legendary bands such as REM. Currently mid-tour, the trio looked razor-sharp, breezily headlining a chilly Sunday. As Quentin Hayes's alluringly sung Cecil tightened the noose, so the drama grew and the tensions tautened.Yet more than the solos, Donizetti's trios and ensembles, always dramatically pertinent, took off, thoughtfully nursed by conductor Sergio La Stella.The queenly fisticuffs over, we badly needed Act III. Despite a couple of awkward cadences, Majella Cullagh - uplifting from her first aria with sighing horns - succeeded in opening out the pacing, so that the great penultimate scene heralding the fall of the axe became one beautifully managed, seamless web The emotion was searing.

Here, where Elizabeth wields the pen and Mary, acquiescing in her fate, makes her confession, the evening gathered strength with intimacy and soared to a new plane. While subdued for the men, Elizabeth sported yellow for her preening first entry, pouted in emerald green at Fotheringhay, and donned rich, velvety blue for the signing scene; Mary's regal authority and beckoning doom alike was epitomised in bright crimson.There was marked warmth from Talbot (the splendid Jonathan Best, here rather oddly bearded and limply directed); likewise Adrian Dwyer's hapless, mellifluous Leicester, hot-headedly eager to surge into aria, but crushed between two equally intransigent lovers. Maria Stuarda needs aching emotion; here, it got it.Chris Davey's pinpoint-accurate spotlighting was the high point of a serviceable staging. By contrast, when designer George Souglides's roped-off Fotheringhay set was unveiled, you felt that sinking feeling. A swaying pendulum and a crop of pikes and halberds seemed the sum total of imagery; scarcely a rich harvest. The telling touches included the ghostly presence of each queen hovering ominously during the other's scene: Mary like an embodied conscience as the action opens; Elizabeth after the warrant is signed.

A children's masque evoking Mary's reminiscence of childhood - the girl ominously blindfolded for their game; a nasty glimpse of the end of come.The costumes - oddly mixed; you wouldn't think Talbot and Cecil belonged to the same century - drew on stark, single colours. If one early aria felt fractionally pinched, Kelly's recitative resonated superbly. Elizabeth's most telling moment came not in the set-to with her cousin as later on, in the great scene where Cecil prevails on her to autograph Mary's death warrant: "E morta ogni pieta," she mutters ("All pity is dead"); and Kelly's voice took on a wonderful hollow quality. Centred on Elizabeth I's dilemma that culminates in the execution of her Catholic cousin, its Schiller-based libretto pits the two feisty queens in a screaming match onstage - preserved on video with Janet Baker and Rosalind Plowright in the Copley/Mackerras production.