HOWZAT

The metaphor-rich writing is, I suggest, out of keeping with the times. Was her voice inspired by a particular author? “I was lucky enough that I didn’t know what voice was, really, when I started writing it,” she says. “A lot of people on creative-writing courses get hung up on ‘voice’, as if it’s something you can drop into writing. But I think it’s something you can discuss only once a work is finished. It’s not like a plot. I think not knowing what the concept was was very helpful to me. I was never anxious that a word or passage wouldn’t fit.”

She must have had some idea of how she wanted the novel to sound? “Yeah, I did,” she says. “The best way of explaining it is to say that my approach was very lexical. I made a lot of notes when I was writing The Rehearsal, and I felt there was a pool of words that should be in the book. For instance, when I came across this word ‘congeal’ in a book called The Theatre and Its Double, I just knew it had to be in there.

“I’d read a lot of 18th- and 19th-century novels by the time I started The Rehearsal, stuff like George Eliot, but had never done a course on 20th-century fiction,” she continues. “If there was one modern author who really inspired me, it was Alan Moore, who wrote the Watchmen graphic novels. He’s supersmart and, in any panel, can have four different layers of reality existing at the same time. I was really, really excited by him. He’s inspired me.”

The complaint often levelled against The Rehearsal is that it tries too hard to be super-smart. Is that fair?

“It’s a criticism I anticipated,” says Catton. “It is an odd book, and I guess I lost a sense of its strangeness very early on. But I think posturing and strangeness in a book has to earn its right to be there. And I disagree that it’s all head and no heart. It’s got a lot of heart. I’ve got real affection for the plight of my characters, and particularly ­Isolde, who’s the youngest sister, like me.

“One of the things people balk at now, but which was very normal for 18th- and 19th-century novels, is the idea that novels should offer any kind of moral instruction. They go to them for entertainment or to see something beautiful, but they don’t want to be chastised by the author for the way they live their lives. I don’t know about that. I feel like I’ve learnt a lot about how to live by reading novels.”

Does The Rehearsal have a moral?

“Ah, shivers, I don’t know,” Catton laughs. “Maybe what’s at the heart of it is that I don’t think truth and fiction, or innocence and experience, are separable. In my novel, if two girls have a love affair that is a copy of an affair [of an older couple], it doesn’t make it less authentic just because it’s a copy. The moral is something to do with that, to do with authenticity.”

Perhaps readers resist taking instruction from someone so young. Does Catton look back at her book now and wish she’d done anything differently?

“My style of writing has changed a lot since I wrote it,” she says. “I do read it now and think, ‘I would never make those choices today.’ But I feel like I couldn’t have written it any later. The Rehear­sal carried me through some of the intensity of feeling that I had back then. Maybe I will look back on it in the future and think differently about it. Pretty much everything else I did in the two years I was writing it now fills me with revulsion, so it’s a possibility. But I haven’t been embarrassed by it, yet.”

In keeping with the wildness of her approach to writing, Catton has spun off in many different directions for her next books. She is writing a “literary novel” set during the 1860s Kiwi gold rush, and a quartet of “young adult fantasy novels” set during the English civil war, “a period I love”.

These choices are more proof, if The Rehearsal were not enough, that Catton is no literary fashion victim. It is a quality entirely in keeping with her character. Ask her, for instance, whether she would have been a Roundhead or a Cavalier, and she shoots back the answer: “I guess you’d expect someone my age to be anti-Royalist, but I’d have to say Cavalier.” Her reason? Roundheads were “joyless”. Catton, most definitely, is not.

The Rehearsal is published by Granta at £12.99

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