PERFECTIONIST director Michael Mann doffs his fedora to Depression-era bank robber John Dillinger in this beautifully-crafted biopic.

Public Enemies surveys a volatile period in America’s history when a group of hoodlums ran rings around J Edgar Hoover and his fledgling Federal Bureau of Investigation.

The battle of wits between the criminal fraternity and the police continues Mann’s fascination with men operating on the fringes of the law, echoing his earlier work in Heat and Miami Vice.

Here, however, there’s a noticeable imbalance in the screenplay co-written by Ronan Bennett and Ann Biderman.

While Dillinger is swaggering and charismatic, brought vividly to life through Johnny Depp’s eye-catching performance, his chief pursuer – agent Melvin Purvis – is cold and lifeless.

As portrayed by Christian Bale, the lawman is mechanical and almost devoid of emotion.

It would come as no surprise if, in the final frames, Purvis turned to the camera and revealed that he was an automaton sent back in time from Bale’s other summer blockbuster, Terminator Salvation.

Mann begins at the Indiana State Penitentiary where Dillinger (Depp) and associate “Red” Hamilton (Clarke) spring a number of their cohorts from the slammer, including Harry Pierpoint (Wenham) and Homer Van Meter (Dorff).

“Let’s go to Chicago, make some money,” roars Dillinger as the gang heads west, relieving the banks of their savings to the embarrassment of the boys in blue.

Hoover (Crudup) pledges to capture America’s first public enemy number one as a demonstration of his department’s ability, enlisting tenacious agent Purvis to lead the nationwide hunt.