Un Ballo in Maschera is famously based on the assassination of a real-life king, Sweden’s Gustavus III, in precisely the way – shot at a masked ball – depicted in the opera. But at a time when Verdi was forbidden to present the murder of a monarch on stage, he turned the doomed hero into the (somewhat unlikely) figure of the English Governor of Colonial Massachusetts.

In his enjoyable new production for Holland Park, director Martin Lloyd-Evans maintains the American setting but updates the action to the present. Thus our Gustavo (we get the names of Verdi’s original version, rather than those of the Boston rewrite) is transformed into the US President, a figure played with reduced vocal force – after his being forced to withdraw altogether in the first days of the run – by the fine Mexican tenor Rafael Rojas.

His loyal sidekick Ankarström (Olafur Sigurdarson), who comes to side with the conspiracy against his boss in the mistaken belief that he has been cuckolded, is presented as an efficient Mr Fix-It in the mould, say, of a Secretary of State.

There were chunterings about the revamp all around me during the interval, with the restyling of the charlatan sorceress Ulrika (powerfully sung by contralto Carole Wilson) into a TV pundit of the Mystic Meg variety attracting particular ire.

It was odd, I admit, to find the sprightly breeches role of the page Oscar – so sweetly sung by Gail Pearson – no longer a breeches role at all as ‘he’ becomes a female PR gofer.

But I thought, on the whole, that the changes worked rather well plot-wise – even if it was a bit odd to see a president so off the lead as to be able to wander incognito in a ‘crack alley’ for what turns out to be his fatal meeting with Ankarström’s doting-but-holding-herself-back wife Amelia. This tortured character is superbly portrayed by South African soprano Amanda Echalaz (pictured. A favourite with the Holland Park crowd, she has twice been winner of the Friends’ award for Best Female in a Leading Role. I would not be surprised if she makes it a hat-trick this year.

There are further performances under conductor Peter Robinson tomorrow, Tuesday, and next Thursday and Saturday. Box office: 0845 230 9769 (www.ohp.rbkc.gov.uk).