When Verdi planned Un Ballo in Maschera (A Masked Ball), his setting reflected the plot's historical basis in the assassination of King Gustav III of Sweden in 1792. But the Italian censors wouldn't have it, so the scenario was transferred – not without losses in likelihood – to 17th-century Boston. In his production for Opera Holland Park, director Martin Lloyd-Evans sticks to the US but forwards the period to that of a recent American president, with characteristics borrowed from Kennedy and Clinton.

Some elements of the new setting – conjured with a fair degree of realism by designer Jamie Vartan – work better than others. Verdi's medium, Ulrica, becomes a TV fortune-teller, indelibly presented in Carole Wilson's sharply drawn and impressively sung portrayal. But when Amelia is sent off to what was, in Verdi's scheme, a lonely place of execution, to find the herb that will cure her illicit passion for her husband's boss, we find her shooting up in a dodgy neighbourhood surrounded by gun-toting drug-dealers leering out of waste bins. Credibility sags somewhat. Sweden might have been a better bet, after all.

The first night was hampered by the indisposition of tenor Rafael Rojas, in the pivotal role of Gustavo, who gamely mimed the part on stage while David Rendall, singing from the pit, gave good value. On stage, rising soprano star Amanda Echalaz sounded almost ready for Amelia, getting through on flair rather than genuine vocal command. Olafur Sigurdarson gave a brash but full-bodied account of her jealous husband. Gail Pearson was a reliable rather than sparky Oscar – here Gustavo's PA, rather than his page – while Peter Robinson's conducting needed more attention to detail.

In rep until 8 August. Box office: 0845 230 9769.