Checkmate - Malorie Blackman

Can the future ever erase the past? Rose has a Cross mother and a nought father in a society where the pale-skinned noughts are treated as inferiors and those with dual heritage face a life-long battle against deep-rooted prejudices. Sephy, her mother, has told Rose virtually nothing about her father, but as Rose grows into a young adult, she unexpectedly discovers the truth about her parentage and becomes determined to find out more. But her father's family has a complicated history - one tied up with the fight for equality for the nought population. And as Rose takes her first steps away from Sephy and into this world, she finds herself drawn inexorably into more and more danger. Suddenly it's a game of very high stakes that can only have one winner . . .

The powerful third story in the Noughts & Crosses sequence.