Adaptation of playwright, novelist, and political rogue Brendan Behan's autobiographical tale. In 1939, 16-year-old IRA recruit Behan (Shawn Hatosy), hides TNT in his trousers and boards a ferry for England, eager to further the Irish Republic's cause. Nabbed immediately by police, the underage Behan evades the hangman's noose, and is sentenced to four years at an English 'Borstal', or reform school, run by the paternal Governor Joyce (Michael York).

The cocky idealist, now living with the enemy - troubled boys that Brendan finds remarkably similar to himself - quickly begins planning his escape. To his dismay, Brendan becomes the object of handsome thief Charlie Millwall's (Danny Dyer) wistful homosexual affections. The young Irishman fights these affections but, in spite of himself, grows closer to Charlie.

Meanwhile, Brendan begins a tenuous relationship with Joyce's daughter, Elizabeth (Eva Birthistle), a literate and upper-crust painter.