"Noughts and Crosses" is about a black girl called Sephy and a white boy called Callum and their friendship in a world that's divided by the colour of your skin - and how their feelings for each other grow as they grow older and grow up. As Malorie Blackman herself says: 'I wanted to turn society as we know it on its head, with new names for the major divisions, ie Noughts (the underclass) and Crosses (the majority, ruling society). I wanted to see this new world through the eyes of the main two characters, Callum (a nought) and Sephy (a Cross). '