The body of a missing child is found with a note reading 'They Must be Destroyed' - a terrifying echo for DS Brooks of an old case in which he was involved. Andrew Dillon - an out and out racist - was convicted six years ago of killing three young boys in similar circumstances. With Dillon safely locked up in prison, it looks like there may be a copycat killer picking up where Dillon left off. Or could there be an alternative and more terrifying truth?