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 after Carl threatens his family; Casey puts her trust in a friend to hide her from Carl.

Chris plans to hand the drugs in, until Carl makes him an offer he cannot refuse; Rachel strikes a deal with Mullen, but Chris' behaviour makes her feel conflicted.

After witnessing Carl's murder, Chris hits rock bottom; Rachel begins to suspect Mullen may not be all he appears; 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, but when Rachel needs his help urgently, Chris must decide where his loyalties truly lie.

Chris is released by Gallagher's men, but finds himself overwhelmed by what he went through. As he manages to pull himself out of trouble, things get complicated as Rachel now knows how corrupt he is.