From BBC Radio 4. Written by Malorie Blackman; Full-cast dramatisation; Dramatised by Janice Okoh.

Callum and Sephy have known each other since they were babies, when his Mum worked for hers. But Callum is a Nought - a colourles second class citizen - and Sephy a Cross, one of the dark-skinned elite. Her father is also one of the country's leading policiticians. No matter how much they may want to be together, the world is telling them they can't. And soon bigger things will prevail. Like the bombing...

Sephy ..... Zawe Ashton
Callum ..... Rikki Lawton
Meggie/Jasmine ..... Adjoa Andoh
Ryan/Andrew Dorn ..... Carl Prekopp
Jude ..... Alex Lanipekun
Lynette/Sarah ..... Tracy Wiles
Kamal ..... Jude Akuwudike
Kelani Adams ..... Nikki Amuka Bird
Mr Pingule ..... Israel Oyelumade
Mr Stoll ..... Richard Pepple
Soanes ..... Gerard McDermott
Shania ..... Victoria Inez Hardy