Even before the first notes are sung, everything about Prince Consort Ladygirl bespeaks erudition. It’s an opera, a Chinese opera no less - possibly the first ever to be performed by Oxford students. In fact it’s a Huangmei opera, a particular genre rooted in folk songs and traditions of that region. Huangmei operas grew in popularity over the last 200 years, and this one (normally rendered Female Consort Prince) is one of the most enduring and popular. As well as on stage, it’s been made into films and mangas. And now director and co-translator William Want has made it into an Oxford operetta.

I’m guessing that Want is a student of Chinese. From his fascinating, self-effacing mini-dissertation in the programme, to the presence, in the on-stage musical ensemble, of traditional instruments like the erhu, the dizi, the bangu and the yangqin, a deep knowledge and love of Chinese culture suffuse every facet of this show. I may have used this phrase before, but you can’t keep it down: Only In Oxford. Where else do you find young people who combine such deep academic interest with such imaginative, entrepreneurial spirit?

And it’s not just Want. He is surrounded by translators, actors, singers, dancers and musicians, all of whom don’t just put on the show: they embrace it. They embody it. They embed in it.

So Prince Consort Ladygirl is a bit of a one-off. But is this production all knowledge and no swagger? A lecture with real people instead of a powerpoint? Or is it a theatrical, operatic revelation? And will its authenticity finally move British audiences on from Miss Saigon and The Mikado?

The story is a classic, Mulan-esque legend taken to comic proportions: Feng Suzhen (a miraculously made-up Lily Zhang) disguises herself as a man in order to free her true-beloved Li Zhaoting (Jedidiah Olaleye). But she ends up betrothed to marry the Emperor’s daughter – and in the process discovers that her brother Feng Shaoying (Zoe Lim) is already in disguise as a woman at the palace. As you can imagine, it all gets sorted out in the end, no one gets executed, and the proceedings conclude with a double marriage. Think Twelfth Night with incredibly long sleeves.

The music is authentic and bewitching. Those traditional instruments (where the hell did they even get them by the way? And how did they find students who could play them? Only in Oxford...) transport you instantly to the Qing dynasty. And the costumes are simply astonishing. They’re so detailed and grandiose, you could almost believe William Want and Costume Designer Jade Bivens stole them from the Ashmolean Museum. And I’m no expert, but even the actors’ movement seems, at times, to be inflected with the long-studied precision of Chinese traditional theatre. Lily Zhang, in the title role, kinks every joint in her fingers to an angle that looks both symbolic and balletic.

On top of that, the creative team has taken the trouble to do more than just present us with an old opera. The translation (when you can hear the words, of which more later) merges modern university terminology with ancient Chinese academia. So our intrepid heroine has to attend tutorials and borrow books from the Faculty of Asian & Middle Eastern Studies. And the gender-querying nature of the original text is given turbo-charged vigour, through the re-translated title, the script and the casting. All the lovers are played by women, including those that are only acting as women pretending to be men. And the playful translation includes such tongue-in-cheek teases as ‘Oh no, the Emperor cannot be a homosexual.’

But perhaps the greatest coup d’operetta of the evening belongs to Peregrine Neger’s phenomenal costume as the Emperor himself. Hoops, castles, rich brocade and apparently bottomless sleeves teeter around his flimsy frame. He looks like a man who loves to dress up, which suits the theme of this production perfectly. He also utters a line which speaks to the one major defect of the whole show: ‘In a play, trivial imperfections can sometimes be tolerated’.

In Prince Consort Ladygirl that trivial imperfection is audibility. The brief spoken sections are admirably clear and enjoyable, but they pop out of the rest of the opera like unexpected signposts on an empty road. For the rest of the time, even though they are singing in English, the cast are essentially impossible to understand.

This is down to several factors: the music, for all its beauty, is simply much louder than the voices; the microphones, worn clipped to the faces of the actors, don’t punch enough volume to compete; the rustling of material, and nasal huffing and puffing, when amplified, often drown out words; and it’s a feature of this genre that the violin plays the exact musical line as the voice, meaning they tend to cancel each other out. But overpowering all these other factors is the one that gets you every time: the notorious acoustics of the O’Reilly Theatre. It’s a booming, echoey space, and few productions are able to wrestle its fearsome frequencies into submission.

One solution would have been to use surtitles. And it’s a shame Red Threaded Theatre didn’t try that, because they would have enabled the audience not only to understand what was happening, but to enjoy the witty detail of the translation. Audibility is only one problem in an otherwise fascinating and vitally different production. But unfortunately it literally prevents viewers from being able to engage with the material. We are sitting on the outside, like English tourists: politely impressed but fundamentally excluded. Let us in!

If the team behind this production chooses to bring us another Huangmei opera – and I fervently hope that they do – then they’re already 80% there. Get the last bit right, and we’ll really be able to appreciate this astonishing achievement.