The difficult 1930s is a time of robbers who knock over banks and other rich targets with alarming frequency. Of them, none is more notorious than John Dillinger, whose gang plies its trade with cunning efficiency against big businesses while leaving ordinary citizens alone. As Dillinger becomes a folk hero, FBI head J. Edger Hoover is determined to stop his ilk by assigning ace agent Melvin Purvis to hunt down Dillinger. As Purvis struggles with the manhunt's realities, Dillinger himself faces an ominous future with the loss of friends, dwindling options and a changing world of organized crime with no room for him.
The film opens in 1933 as John Dillinger (Johnny Depp) is brought to the Indiana State Prison by his partner John "Red" Hamilton (Jason Clarke), under the disguise of a prisoner drop (with Dillinger posing as the prisoner). Inside the prison, several gang members, Charles Makley (Christian Stolte), Harry Pierpont (David Wenham), Ed Shouse (Michael Vieau), Homer Van Meter (Stephen Dorff), and Walter Dietrich (James Russo) acquire guns smuggled into the prison inside boxes....