Jackie Peyton, a strong-willed and brilliant but very flawed emergency room nurse. This season, Jackie comes to realize that both karma and sobriety can be a pain. In addition to finally confronting her addiction, Jackie's street smarts and sardonic wit are tested even further by an ambitious new hospital administrator determined to run a tight ship and keep Jackie in line.

Jackie realizes sobriety is the ultimate cover for getting high, and now she's saving lives at work, taking care of her kids, and her boyfriend is loving the new her. She's got everyone fooled, but what goes up must come down.