The movie, which centers on the 1930s figure Ma Barker and her criminal sons, was filmed in Guthrie, Oklahoma.

She marries decent George Barker and gives birth to four sons, Herman, Arthur ("Doc"), Lloyd and Freddie.

However, when George's law-abiding ways fail to provide for the family, "Ma" encourages her sons to commit crimes.

FBI leader, J Edgar Hoover puts agent Melvin Purvis on the case.

Arthur Dunlop, a corrupt prison guard, helps Freddie escape and becomes Ma's lover.