When Dorothy Guildford is found stabbed to death in her leafy suburban home, all signs point to the husband. But forensic pathologist Doctor Rosie Fergusson is convinced there's more to this case than meets the eye.

While searching for evidence that will put Peter Guildford behind bars for good, DC Kirsty Wilson and the CID team unearth a link with a human-trafficking operation that Detective Superintendent William Lorimer has been investigating for months. But before they can interrogate Peter further, he is brutally attacked in prison.

Lorimer and Kirsty team up to find out as much as they can about Peter, the attack and how it all connects to the mysterious 'Max' who it seems is at the centre of the trafficking ring. But the stakes get higher still when a young Slovakian woman and one of MIT's undercover agents are kidnapped by the very man they seek . . .