Tom Mallory is a respected employee of the MoD and a sleeper agent secretly working for the KGB. Tom's got high level access to state secrets, and when he discovers the contents of a top-secret letter, he could leave the UK vulnerable to a nuclear at... (more)tack. Daddy and the team must find him, turn him and stop him before he shatters the precarious peace of the Cold War. Meanwhile, Joe is haunted by events in his past, his lover's killer is in London and he is deeply embroiled in Operation Glass. Can he put his personal vendetta to one side, or will it jeopardise his part in the investigation?