Postal Inspector MC McCall struggles to find her footing after the murder of her partner. Nearly four months after losing Barb, MC finds it difficult to keep her distance from the investigation into Barb's death. The homicide detective in charge doesn't mince words to let MC know she needs to stay behind the yellow tape on this one and let him do his job. MC throws herself into her own investigations-or tries to, anyway. She's often not on time to work because of too many late nights with the vodka bottle. And her supervisor makes it clear that he'd love nothing more than to force her out. MC's co-workers and close friends notice her sliding down a slippery slope. They reach out, try to throw her a lifeline, but this only pushes MC farther away so she is more hellbent on handling things alone. Will an assignment investigating a potential drug scam along the North Shore be the ticket to keep her on track? Or will MC spiral into a personal and professional darkness from which she'll not be able to come back?