The villain in Black Op is an ex England football star called Jim Sells.
Jim Sells (fictional) used to play for Spartak Moscow in Russia and - while there - he is corrupted and begins working for the KGB, then FSB.
In my book, he is the coach of an England youth team. He is also a spy master for five children who are using the team as their cover story.
But, when I was planning the book, Jim Sells (fictional) was good. He was based on my friend and National Literacy Trust hero, er... Jim Sells (real). He would coach the children in football and spycraft and help them save the England football team from certain death.
Jim Sells (fictional) was also slightly based on the author James Riordan, whose book Comrade Jim describes how he played for Spartak in the 50s while mixing with known spies and double agents. Great book. Sadly, Riordan died recently. I was lucky to meet him once.
When I was writing the book, Jim Sells (fictional) suddenly turned and betrayed the five children he was nurturing. It turns out he was working for the Russian secret services.
I'm not sure why. It just happened. One minute the children were looking for Sells, knowing he was in danger. The next minute, he was on a chopper from Poland to Moscow, having left them in a very perilous situation.
It was strange and hard to write, because Jim Sells (real) is such a nice man. But that's what happened.
My favourite author - Emile Zola - wrote an essay once, saying he set his characters off and let them do what they needed to do and that it wasn't really down to him. I had that in mind when I wrote it.
Of course, I'm no Emile Zola.
And I must stress Jim Sells (real) is no Jim Sells (fictional) ... as far as I know.
Black Op is published tomorrow by Puffin Books.