Two people on opposite sides of the law are brought together under unusual circumstances in this thriller. Lea (Elsa Zylberstein) is a young woman with a checkered past who has just finished a stretch in prison and is waiting for her teenaged brother, Sammy (Vincent Martinez), to pick her up. As it turns out, Sammy has been nurturing an impressive criminal career of his own, and he's killed in an ambush with plainclothes police officers within Lea's sight. Traumatized, Lea isn't sure where to turn, and finds solace in the arms of David (Richard Berry), a police detective who is dealing with a crisis of his own -- he confiscated two kilos of heroin during a drug bust, which ruthless criminal, Zak (Pascal Greggory), is demanding as ransom after kidnapping David's nine-month-old son. While their tragedies have brought them together, what Lea doesn't know is that David is the policeman who shot her brother, and soon they both find themselves at odds with one another's allies in the French criminal underworld. Un Ange was a rare foray into theatrical filmmaking for established television director Miguel Courtois.