Mercy is an ensemble drama set in the fictional Mercy Hospital in Jersey City, New Jersey. The show focuses on the lives of three nurses. Veronica Flanagan Callahan is a nurse who has just returned from a tour of duty in Iraq, while Sonia Jimenez, her best friend, has become seriously involved with a police officer, and Chloe Payne is a recent nursing graduate who is thrown into the world of nursing and is unprepared for what it entails.