Every year, the Opera Holland Park season has included a little-performed opera by one of Puccini's contemporaries, a tradition with which I’ve been more than happy: Catalani’s La Wally and Mascagni’s Iris have been gems, and while there have been others that haven’t blown me away, I’ve always been interested to see what they were like. Mascagni’s Isabeau, I fear, has been a step too far: there are some operas that languish unperformed for good reason, and this is one of them.

Isabeau is a retelling of the Lady Godiva story. The evil, or at least misguided, King Raimondo punishes his daughter by ordering that she ride naked through the city. Under pressure from his outraged subjects, Raimondo softens the punishment so that everyone must close their windows and eyes, on pain of being blinded. Everyone complies except Folco (“Peeping Tom” in the original legend), who is attacked by the mob who are only too keen to exact the prescribed punishment, and things go downhill from there.

Brought up on El Cid and its ilk since childhood, I’m as much of a sucker as anyone I know for medieval costume drama, and I’m pretty tolerant of opera’s countless plot vagaries, but I found the plot of Isabeau impossible to swallow. The original legend is strong enough, with Lady Godiva making the ride as a noble gesture to rid the folk of Coventry from oppressive taxation. Unfortunately, Mascagni and librettist Luigi Illica choose to ignore the nobility of her gesture and concoct some hokum about the punishment resulting from Isabeau effectively refusing to marry anyone and thus maintain the royal line, together with some even more arrant nonsense about Folco being a poor woodcutter whose grandmother persuades him to become a falconer in the Princess’s service (of course, being a tenor, he falls in love with her). Opera plots don’t need to be credible, but they need to make sense on some level – emotional, perhaps, tragic or poetic. Isabeau’s libretto had me cringing from start to end.

It’s just about possible, although improbable, that a perfect, engaging production might have made me have some sympathy for the piece, but Martin Lloyd-Evans’ staging wasn’t it. Things didn’t start well with a drastic scenery malfunction, following a trumpet and timpani fanfare that swamped the unfortunate herald (I can’t imagine what possessed Mascagni to make the herald sing on top of the brass rather than in the gaps). The set, by designer takis, was functional enough, if somewhat overly fussy with multiple bits of city being wheeled around the stage. But takis' costumes fell into that awful gap of being obviously of the period, but of insufficient quality to be persuasive: the result was cheap and amateurish. I’m not going to go through a roll call of the many minor production failings, but I will point out that black theatre puppeteers wear black for a reason – it takes them out of the audience’s consciousness – and that medium grey just doesn’t work.

A decent cast of singers did their best. Mikhail Svetlov displayed a huge, stentorian bass voice as Raimondo, Anne Sophie Duprels was committed and well in tune in the title role, David Butt Philip would have sounded good as Folco if he hadn’t been overstraining his voice to make himself heard above a lush orchestration, Fiona Kimm was suitably urgent as Folco’s grandmother Giglietta. The main impression that the orchestra and chorus made on me was that they were punishingly loud; on a hot night, there were also intonation problems.

But with such unpromising starting material, I doubt that Callas and Di Stefano in their prime could have converted me. One to miss.