The informant (1997)

A former Irish Republican Army fighter, Gingy McAnally (Anthony Brophy), is reluctant about being called back into service after serving time in prison. He executes the grisly task but ends up captured by a sympathetic British police lieutenant named Ferris (Cary Elwes). The intimidating Chief Inspector of the Belfast Police (Timothy Dalton) convinces Gingy that his best hope is to become an informant and turn in other IRA operatives. As Gingy's marriage unravels under the stress, he is forced to come to terms with the fact that in this war both sides lose. Three men, three political circles, each fighting for their lives, each with their own agenda in the battle for Northern Ireland.