Season three introduces a new main villain, Robert Quarles of Detroit. The parent criminal organization connected to the Frankfort mafia has exiled Quarles to Kentucky. Quarles begins to muscle in on the local criminals, successfully supplanting them until Raylan begins investigating. Simultaneously, Dickie Bennett, the lone survivor of the Bennett clan, seeks the aid of the black residents of Noble's Holler and their leader Ellstin Limehouse in recovering...

Mary is a hitwoman working for an organized crime family in Boston. Her life is completely turned around when she meets a young boy whose path she crosses when a professional hit goes awry.

After witnessing the brutal murders of a convenience store owner and his son; firefighter Jeremy Coleman nearly escapes with his life. As he is forced to testify against the crime lord, Hagan, he is placed in the witness protection program under the watch of the U.S. Marshalls.

Chev Chelios is a professional assassin working for the West Coast crime syndicate. Chev is planning to quit the crime syndicate so he can spend more time with his girlfriend Eve. But for Chev, things go very bad when he learns he has been injected with a poison called "The Beijing Cocktail" by his rival Verona. The poison will kill Chev if his heart rate drops. Chev has to protect Eve and he sets out to find answers as well as exacting revenge on...