After killing Pretty Boy Floyd (Tatum), FBI agent Melvin Purvis (Bale) is promoted by J. Edgar Hoover (Crudup) to lead the hunt for John Dillinger (Depp). Purvis shares Hoover’s belief in using scientific methods to battle crime, ranging from cataloging fingerprints to tapping telephone lines.
In between a series of bank robberies, Dillinger meets Billie Frechette (Cotillard) at a restaurant and woos her by buying her a fur coat. Frechette falls for Dillinger even after he reveals his identity, and the two become inseparable.
Purvis leads a failed ambush at a hotel where he believes Dillinger is staying; an agent is killed by Baby Face Nelson (Graham), who escapes with Tommy Carroll (Garrett)…
