Nikita (Anne Parillaud) is a teenage troublemaker who is addicted to heroin. She tries to rob a pharmacy which is owned by the parents of a fellow heroin addict. The crime goes horribly and Nikita ends up in a gun battle with the police and her friends are killed. While she is having severe withdrawal symptoms, Nikita shoots and kills one of the cops for which she is arrested and put on trial. She is then convicted of murder and sentenced to life in prison and cannot come up for parole for 30 years. While she is in prison she is injected with a drug by the DGSE, the French intelligence agency which makes it appear that she died. She is then given a choice of either working for the organization as an assassin or facing the consequences.