British soldier Jody (Forest Whitaker) is lured by Jude while off duty in Ireland an taken captive by Fergus (Stephan Rea), Jude (Miranda Richardson), Maguire (Adrian Dunbar) and others in the IRA. He is held to be exchanged for a IRA prisoner the British are holding. During the three days Jody is held, he and Fergus become friendly as they talk about their lives and Ferguson shows care by removing the canvass sack on his head. Jody tells Fergus about his girlfriend back in London named Dil. Jody says she is his type of woman. Jody tells Fergus he won't shoot him when it's time because it's not in Fergus' nature. He tells him a parable about the scorpion and the frog. The scorpion asks the frog to take him across the river because the scorpion can't swim. The frog says no because you'll sting me. The scorpion says trust me. Half way across, the frog feels a sharp sting and says to the scorpion as they sink, why did you sting me? Now we'll both drown. I couldn't help it, said the scorpion, it's in my nature. Jody has Ferguson take his wallet with Dil's picture and asks him to go to her place of work or local bar and tell her he was thinking of her at the end. Finally, when it becomes time to shoot Jody, Fergus takes him out into the woods, takes off the hood, but can't shoot him. Jody breaks his bonds and runs away from Fergus. Jody runs onto a road and is hit by one and run over by a second British armored carrier. The carrier and assault troops are attacking the house where Jody was being held. Two IRA members are killed in the attack except Fergus, Jude and Macguire. Fergus decides to disappear and go to London and find Dil. He arranges to get to London and begins working as a day laborer. He goes to the place where Dil works as a hair dresser, has his hair cut and then follows her to "The Metro," a corner bar. Col (Jim Broadbent) is the bartender and he begins the discussion between Dil and Fergus, who is now using the name Jimmie. But soon the two of them are talking to one another. Another man comes up to Dil and drags her out and down the street. Fergus follows them as they go to Dil's apartment and he sits outside and watches them embrace in the window shadows in her flat. Fergus goes to the bar a second time and again talks with Dil after she does a number on the stage and her boyfriend come up. The boyfriend grabs Dil and they go outside and down an alley. Fergus follows them and he defends Dil and knocks the other man down and asks Dil what she would like him to do with the boyfriend. They leave him and go back to Dil's flat. Later the boyfriend shows up outside Dil's flat and she throws all his clothes and possessions out the window. Jimmie asks Dil about the man in a number of pictures in her flat. The man is Jody and Dil says he is a soldier and he is different from the others. Jimmie and Dil begin making out and Jimmie begins to run his hand up Dil's skirt, but she stops him and then performs oral sex on him. She says he can't stay over and they arrange a date for the next day. They go for dinner and end up back at Dil's flat and lie down on the bed. Dil goes into the bathroom and changes into a robe. She returns and Jimmie opens the robe discovers that Dil is a male with a penis. Jimmie is repulsed and hits Dil's as he gets up and heads into the bathroom and vomits in the sink. Dil realizes then that Jimmie was unaware she was a male. Jimmie leaves the flat while Dil pleads with him to stay. After thinking about Dil That night, Jimmie realizes he still cares and writes a letter of apology to Dil and puts it in her mail box. Dil shows up at Jimmie's work site and they talk and reconcile and agre to meet later. Upon his return to his flat, Fergus discovers Jude waiting for him. He thought she had been killed in the attack. She said they were going to kill him for messing up, but they were impressed he had disappeared and was a hidden resource. Fergus asks to be left alone but Jude reminds him there is no quitting the IRA. He is told he will be part of an assasination assignment on a man in London. Fergus realizes he has no choice and Jude makes it clear they are watching Dil, and if Fergus doesn't cooperate she will be harmed. Ferguson goes to warn Dil's and finds Jude at the hair shop getting her hair done by Dil. Jude then follows the pair and they have a confrontation where Dil gets jealous and walks out. Jude and McGuire take Fergus to case the assignment and Dil follows and confronts Fergus. Fergus talks her into cutting her hair and becoming a man and takes her to a hotel to hide. But when he leaves the next day to go to work and meet Jude. Dil leaves the hotel. Dil gets a bottle and heads back to her flat drunk. Fergus intercepts her and they go upstairs where Fergus comforts her. They fall asleep and when Dil awakes, she ties Fergus to the bed to prevent him from leaving after she finds a gun in his coat. Dil holds the gun and gets the truth about Jodie and what happened in Ireland. Jude and Maguire are waiting for Fergus to show and when he doesn't, Maguire tries to do the mission himself and is killed. Jude drives off and heads for Dil's flat. Jude bursts into the flat with her gun but Dil gets off the first shots and kills Jude. Fergus tells her to leave right now and he sits down to wait for the police and cleans the fingerprints off the gun and puts his own on the trigger. The closing scene is in the prison where Fergus is doing time for the murder. Dil comes to visit him and has regrown her hair and they discuss how many days are left in his sentence and they can be together. She asks why he took the murder rap for her. He tells her Jodie's story about the scorpion and the frog. He ends by saying, it's in my nature (to do the right thing).