After treating a family that was involved in a fatal car accident, Dr. Grace Devlin reels when she is ordered by Constantine to tend to the driver of the deadly hit-and-run. Meanwhile, someone from Grace's neighborhood is brought into the psych ward after a bar fight, and Nate makes a critical move.

As she fights for a critically ill woman's heart transplant, Dr. Grace Devlin is asked by Constantine to kill her patient's estranged and imprisoned father in order to get the organ she needs to save her life.