Iris, Opera Holland Park

"Better than Puccini," raved one Tweeter after the final rehearsal of Opera Holland Park's season-opener. Nonsense: "nearly as good as Puccini" is the best any of his Italian contemporaries could hope for; that applies to Leoncavallo and the Cilea of Adriana Lecouvreur.

Mascagni is more arthritic in his sense of movement – think of how long the plot of Cavalleria Rusticana takes to get going – and sometimes strives hard for those orchestral effects which seem so natural in Puccini. But Iris is at least half-interesting, unlike an OHP stinker, Zandonai's Francesca da Rimini, and it's honourably done.

"Honourably" means, from director Olivia Fuchs's perspective, tackling head-on the distasteful plot in which a girl young enough still to be playing with dollies is drugged and carted off by a Japanese version of the Duke of Mantua to the red-light district and subjected to various degradations before being thrown out with the rubbish. It's the woman-as-victim theme in opera relentlessly applied, all the worse since Iris lacks the backbone of Puccini's Cio-Cio San (Iris was premiered in 1898; Madama Butterfly followed in 1904). Fuchs's designer, Soutra Gilmour, substitutes bars for paper screens in the three cubes on stage, and Fuchs has the women trapped in them throughout the horrible Second Act, with just a measure of revenge on the three ghastly principal men by putting them behind the bars as figments of the dying, degraded but at least liberated Iris's imagination in Act Three.

Fuchs's staging of Iris's terrified encounters with playboy Osaka, who's put on a puppet show (shame there weren't really puppets) in Act One to try and seduce her, is unrelenting, and Anne Sophie Duprels (pictured right) is totally convincing as a childlike creature fluttering around painfully to escape what she knows is going to be wrong. Duprels's tone can spread at the top – she's spent many years now singing heavy lirico spinto roles – and in the first act she sang under the note, but the voice was fully engaged by the time of the big conflict, and few sopranos capable of singing the role would go to such physical extremes.

The trouble is that Mascagni shows no musical signs of telling us what a shit Osaka is – Puccini, of course, had consul Sharpless on hand to comment on Pinkerton's behaviour, and at least there was a man who might have thought himself in love as well as lust on his "wedding" night – and revels in the slightly amorphous Italian warmth of his florid language to try and force himself upon poor Iris. So there's a very uncomfortable disjunction between action and song. Fuchs really has no option, but then defuses the nastiness by having Noah Stewart take his shirt off, at which point the Italian girls behind me starting clucking over his pecs. Stewart is very definitely the genuine tenor article, but unrefined and lucky not to crack in his Act One serenade; there's still work on technique to be done.

Act Two's climax, at least, is genuinely upsetting, the male brothel visitors howling over Iris as window-dressing. Here and at both ends of the opera (the apotheosis pictured above), the splendid OHP Chorus sings magnificently. Mascagni's slightly overblown hymns to the sun, with the one tune that may bore itself into your brain by virtue of repetition, go at full pelt, with a combination of drive and grandeur from conductor Stuart Stratford. Not all the players sounded at their best yesterday – the first horn was having a bad night – but the more refined of the textures, the jet-black lower string passages and the whole-tone weirdness at the opening of Act Three, followed up by an evocative Rag-Pickers' chorus, really made their mark.

In passages such as this, Mascagni promises so much that he never quite delivers; the pathos and sentiment that seem to emerge so naturally in Puccini are often unmerited, so it's never quite moving. We can't, for instance, be expected to feel any sympathy for Iris's blind old father, resonantly sung by Mikhail Svetlov; he, James Cleverton as the pimp-villain Kyoto and Johane Ansell's Geisha are the most rock-solid voices on stage. But it's really Duprels's acting and the massed OHP forces which carry the evening – and note that there's more for the chorus to do here than in the whole of ENO's cruelly truncated 2016-17 season. In that respect, Opera Holland Park has the balance right.

• Iris at Investec Opera Holland Park until 18 June