Sex Addict explores the compulsive and destructive nature of sexual addiction and follows Mark and Connie as they battle to deal with Mark's sex addiction. The couple embark on an intensive counselling course, which proves to be an emotional rollercoaster for both of them. Mark is forced to deal with difficult events in his past and Connie must face the lies and deceit that have plagued their relationship. By admitting his problem Mark begins the long process of defeating his compulsion and saving his marriage.