The Best Film --Bar None-- About Northern Ireland
The Informant is the film version of "Field of Blood" by Gerald Seymour. It is quite simply a wonderfully suspenseful story about what happens when a veteran IRA man facing a triple life sentence for the murder of a judge and two detectives in Belfast decides to become a "supergrass" (Cockney rhyming slang for "snake in the grass," in other words an informant, or "tout").
There is no Hollywood idiocy or romanticizing either the British or the IRA in this movie. It shows the viewer in gripping detail exactly what it is like for a terrorist/freedom fighter to turn against his own and the brutal pressures that both the authorities and the terrorists can bring to play upon such a man.
The best part about this movie is that it draws on true stories. In the early 1980s, the British used --initially with enormous success-- the tactic of having a "converted terrorist" testify against his colleagues.
I cannot recommend it highly enough.