Malorie Blackman 
Double Cross 

”Blackman ‘gets’ people . . . she ‘gets’ humanity as a whole, too” Guardian
Just this once. Just this once and no more, I promise.
Please let me get away with it just this once . . .
Tobey wants a better life – for him and for Callie Rose. He wants nothing to do with the violent gangs that rule the world he lives in. But when he”s offered the chance to earn some extra money, how much could it hurt to just this once say ”yes”?
Callie Rose knows all about the danger of saying ‘yes’. She knows about terrible mistakes, and violence and family feuds, and the fierce divide between Noughts and Crosses.
And knowing so much about the past makes her afraid for her future.
Because sometimes, one little bad decision can change everything . . .
”Powerful”
Sunday Times