Ex-Slaughter and May solicitor Jennie Rooney on how she wrote her first novel, 'Inside the Whale', during her training contract

Lots of people talk about doing things, but never actually do them. There's plenty of that at a law firm. It was an odd environment to be working in, where everyone seemed to be thinking about where they'd rather be and what they'd rather be doing. Having started the book – something which admittedly took a while to get round to – I drew confidence from the fact that I was actually pursuing my ambition.

I wrote 'Inside the Whale' during my training contract. It's fair to say that I didn't go out very much that year. When I was at work I'd do whatever tasks I was given, but I wouldn't seek out anything extra. And a six month secondment to Slaughter and May's Paris office, which was less busy than London, proved really useful for getting on with the writing.

The book was inspired by my grandad's experience of the second world war. As told to me by my mum. He went off to Africa with the Royal Signals, before being captured and sent to Italy as a prisoner of war.

When I handed in my notice I still had no book deal. An agent, yes, and a completed book, but no deal. I subsequently got a two book deal. Which means I'm going to have to write another.

My mum and dad were quite keen on law. I'd done history at Cambridge and I thought law would open doors – and, to an extent, it did. Slaughters was a good experience, but writing was what I always wanted to do.

Sometimes I miss the office atmosphere. I didn't think I would, but I do. Sitting in your flat writing can be lonely, but I'm getting into a bit of a routine now.

'Inside the Whale' by Jennie Rooney is published by Chatto & Windus.

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