A deranged businessman snorting rails off a boardroom table; a homoerotic flute-off; and random members of the public popping in and out. This ain't opera like we've ever seen it before.

To call New Zealand Opera's Eight Songs for a Mad King a one-man show would be an injustice. The King (played by the convincingly insane Robert Tucker) interacts freely with the conductor (mad), the six-piece orchestra (mad), and the audience (varying degrees of mad).

The very modern performance takes place in Tūranga, the central library, with the audience split in two. For the first half, we're placed in the audience seated outside (hot tip: wrap up warm – this is Christchurch after all), while half of the punters are directed inside to cosy seats near the upstairs window.

We're assaulted by sound through our headphones – bizarre noises, clacks, scrapings, and melodies. And yelling. Singing and yelling. Singing, and yelling. The show is often described as a 'descent into madness' but it's pretty clear the King is already well on his way from the start as he prances, stomps and crawls around the room, singing, muttering, and riffing off the jazzy beat of the orchestra. He climbs on the table and stares out the window directly at us outside – or is he staring at the crumbled Christ Church Cathedral behind us as he screams "GOD"?

Half the fun of watching from outside is seeing everything else that is going on. A cyclist rides through the plaza between us and the performance, looks at the audience, hears the music, and does a double-take as he torns to look up at the performance as he rolls through. A couple loiter by the corner of the library, unsure how to proceed. The tram rolls past, faces lit up in the windows. A man stops to take a selfie with a penguin sculpture – completely ignoring the madness going on behind him. Meanwhile, the music carries clearly thorugh our headphones (mixed live with creative stereo effects) while being simultaneously broadcast to the world from outside speakers.

It's a short performance – just over 20 minutes – and after an intermission we swap with the inside audience to watch it all over again from a new perspective. Far form being a boring repeat of what we've already seen, watching the performance again up close reveals a whole lot of new details. For one, we're amazed to see all the bizarre sounds we heard being created live by the orchestra and performer – no pre-recorded effects at all.

The King (who we now see is dressed as a businessman) gets interactive early, picking the Cityscape contingent out of the audience for some personal, up-close intimidation. He wades into his orchestra with no regard for personal space. The conductor steps in and out of the performance, and the orchestra take turns glaring at the audience and reacting to the King's actions. At one point the flautist breaks away from his peers to do a little, very intimate, solo and dance with the King.

Drug-and-booze-fuelled and adrenaline-soaked, the King makes no bones about doing permanent damage to his surroundings. As his echoing howls close off the performance, we are left with the crystal-clear appreciation of the potential of opera in the hands of the creative and innovative people at NZ Opera. We don't care whether you've never seen opera in your life of if you're a seasoned appreciator of the art, you should take the opportunity to see this show.

Get in quick – there are a few tickets left for the Saturday and Sunday night performances.

Eight Songs for a Mad King
Tūranga, December 3, 5 & 6
nzopera.com