Liquidator is a thriller. It's an insane, heart-stopping chase-novel, that aims to leave you breathless: a bizarre range of child-heroes work to expose a cynical and hideous crime, perpetrated in a poor African state.

It took Andy two and a half years to write, and after the constant sugar-warnings we receive, it feels ridiculously topical. A multi-national corporation is aiming to addict the world to its brand-new energy drink. What's the drink? - Liquidator. Available in six different flavours, it will set you on fire – not least because the stuff is packed with deeply dodgy stimulants that keep you crawling back for more.

Road tested in the developing world, the drink has already left a trail of destruction, and the company lawyers are burying the evidence. That's the scandal, and the kids crack it wide open.

The working title was WORK EXPERIENCE. Why?

'The book's serious,' says Andy, 'but at its heart there's a kernel of ludicrous comedy. We start with a group of fourteen-year-olds off on a week of work-experience. The drinks company takes on a well-meaning girl, who's desperate to learn.

Unfortunately, she's also clumsy and a chapter of accidents lead her and her friends to untangle terrifying secrets concealed on a laptop. The book emerged from the whole concept of children causing mayhem in the work-place. When I worked as a teacher, I used to supervise such weeks of so-called 'work experience' – and they were all too often a predictable disappointment, as pupils returned to school having experienced only the stranglehold of health and safety concerns.

I always hoped that one day, a would-be surgeon would come rushing back to class, shouting "It was great! I cut someone open!" It never happened in life, so the book plays with that fantasy. The heroes join forces in their different roles to expose the criminals.'

Could this be an ISSUES book? Is it a book young people should be reading?

'It's absolutely not – I can't bear books that set out to create liberal discussion of worthy topics. Such books are usually threadbare. No – if LIQUIDATOR works, it's because of the characters, who come with a wide range of insecurities, intolerances, hopes and fears. Fundamentally it’s an adventure: they risk everything, and to an extent they lose their innocence. It's a terrible shock when you discover the world is so ruthless...'

LIQUIDATOR is published by Pushkin Press, and is available at all good bookshops, or through the usual on-line stores.