A heist gone wrong and the manhunt that follows, provides this movie with its basic plot and a great deal of suspense. The real focus of the story, however, is on the "conflict in the hearts of the people" who are caught in the fall-out from a political struggle and how, in such an environment, basic human charity can become one of the first casualties. The fact that the action is set in Northern Ireland and involves the conflict between the IRA (Irish Republican Army) and the government is purely academic as similar reactions would be likely to be found in any people who unintentionally find themselves involved in any similar type of conflict.
In a terraced house in Belfast, a small group of men under the leadership of Johnny McQueen (James Mason) discuss a plan to carry out a robbery at a local mill in order to raise funds for their organisation. Johnny, who had previously been sentenced to 17 years in prison for gun smuggling had escaped after serving only 8 months and, as a wanted fugitive, had spent the last 6 months indoors to avoid being recaptured. Kathleen Sullivan (Kathleen Ryan), who lives in the house with her grandmother, is deeply in love with Johnny and together with Johnny's second-in-command, Dennis (Robert Beatty), tries to persuade him not to take part in the heist. Kathleen and Dennis share the view of the rest of the gang, that after such an extended period of inactivity, Johnny simply isn't fit enough for the job. Johnny, however, feels it's his duty to be involved and is determined to carry on as planned.
On the day of the robbery, Johnny immediately experiences some disorientation as he travels to the mill and finds it hard to adjust to being out in the city traffic. The robbery goes ahead smoothly and the rest of the gang get back to the getaway car successfully but as they shout to him to get in the car, Johnny becomes dizzy and pauses before being accosted by one of the bank's employees who's brandishing a gun. The two men wrestle and their struggle ends with Johnny injured and his assailant dead. As the getaway car speeds away, Johnny hangs on with the help of a couple of the gang members and desperately tries to get in but fails and is left lying in the road when the gang's driver, who's afraid of being caught, refuses to stop to pick his leader up.
At this stage, it becomes clear that Johnny is seriously wounded and when he manages to pick himself up, stumbles off down an alley and hides in an air-raid shelter. Exhausted, bleeding and realising that the manhunt for him is closing in, he feels trapped and incapable of going any further until Dennis finds him and by taking action to attract the attention of the police, gives Johnny the opportunity to try to make his way back to Kathleen's house. This proves to be the beginning of an arduous journey during which he encounters a whole variety of characters who either don't want him around when they realise who he is or try to exploit him in various ways. Kathleen meanwhile makes arrangements to escape to a new life with Johnny but when she tracks him down, encounters some problems in putting her plan into action.
James Mason gives a remarkable performance as a man whose fate was decided when his idealism led him into a violent political conflict and the high risk of becoming a killer. Interestingly though, some facets of his personality and behaviour also display some more noble qualities and surprisingly make him a more sympathetic character than anyone would normally expect a killer, criminal or terrorist to be. Kathleen Ryan also makes an indelible impression as the woman who bears the burden of falling hopelessly in love with Johnny and with great dignity and determination, does everything within her power to ensure that he gets away from the city for a better life somewhere else. The high quality of Mason's and Ryan's work is also well complemented by the other cast members who all do exceptionally well in their various roles.
It's noticeable that as Johnny's efforts to escape his pursuers become ever more desperate and dangerous, the darkness and bad weather that engulf the city, symbolically, make it appear increasingly claustrophobic and threatening and the ways in which this is portrayed on-screen are visually impressive, technically brilliant and extremely rich in atmosphere.