My latest novel is about three women who become mystery shoppers - going undercover to investigate the best, and worst, in customer services.

New mum Emily wants revenge on the stick-thin assistants who laugh at her post-baby tummy and post-baby budget. But frumpiness has its advantages when you're wielding a secret camera - and sending the damning footage straight to head office. Store manager Sandie has a lifelong love of the world of retail - the glitz, the glamour, the stockroom. Then she's fitted up by an ambitious assistant and secret shopping is the only way to keep her one passion alive. Glamorous widow Grazia can't leave behind the high life, despite her chronically low bank balance. The more she's buying - and spying - the less time she has to mourn her husband or her fair-weather friends who've dumped her. They're Charlie's Shopping Angels, controlled by a mysterious figure who sends them assignments. But when they're sent to stitch up a doomed shop owned by Will, the angels begin to feel divided loyalties . . .

Themes:

You might expect that a novelist writing a book about shopping would adore browsing and trying on shoes and clothes. But I was born without the shopping gene. I adore shopping online (even though the security code has almost worn off my credit card) but I find the whole ordeal of Oxford Street before Christmas about as tempting as a Polar expedition wearing flip-flops. I don't mind going for a bit of a mooch around John Lewis and Selfridges on a quiet afternoon - in fact, there's something about the theatre of those stores that is magnetic - but only if I have nothing I need to buy.

I also used to work in a kitchen and hardware when I was seventeen, selling saucepans to posh, grumpy ladies, so I have experience on the other side of the till as well. My experiences of terrible service - and occasionally giving terrible service myself - have counted as research for the book.

But before I wrote novels, I also worked as an undercover journalist, so I really enjoyed writing about the anxious moments and nerves involved in pretending to be something you're not…

Topics for discussion:

• What does good customer service mean to you? And what's the worst experience you've ever had in a store? Are there any places you avoid forever after a humiliating moment in the changing rooms or at the tills? In the novel, Emily is targeted for a hard sell - can that ever be justified?
• Do you feel it's fair to spy on employees under any circumstances? Some mystery shopping assignments even ask the shoppers to rate the authenticity of the staff member's smile! Is it reasonable to expect store or fast food staff (some of whom are earning really low wages) to be one hundred per cent enthusiastic all the time?
• Sandie is a workaholic until she's sacked - how can a passion for your day job affect your personal life? And would you rather do your dream job, or have a happy home life? Can women have a balance?
• What's your view on workplace romances - can they ever work, especially between rivals? And have you ever worked with a partner?
• The narrative of Secret Shopper's Revenge is split between three characters, all in the first person? Which woman's attitude to shopping was closest to your own, and why?