CID officer Nick Bailey’s condition worsens as Tracy struggles to protect local residents against the numerous deposits of Novichok being found across the city.
The Skripals and DS Bailey fight to survive, and Tracy and the emergency services try to locate the source of the nerve agent to prevent further casualties.
Several months later, the city is starting to forget and heal - until a scavenged perfume bottle leads to tragic consequences for Dawn and Charlie.
Chris plans to hand the drugs in, until Carl makes him an offer he can’t refuse. Rachel strikes a deal with Mullen, but Chris' behaviour makes her feel conflicted.
Chris reaches rock bottom. Rachel begins to suspect Mullen may not be all he appears, and Casey teams up with Marco to find a buyer.
Chris is forced to work for a major drug dealer to return the drugs stolen by Casey. When Rachel needs his help urgently, Chris must decide where his loyalties truly lie.
Police response officer Chris is struggling to keep a grip on his mental health and marriage when he is offered a path to redemption in the form of a young heroin addict.
Chris must juggle rookie Rachel while tracking down Casey. Casey puts her trust in a friend to hide her from Carl.