Léon: The Professional, titled Leon in the UK and Australia, is a 1994 English-language French action-thriller film written and directed by Luc Besson. It stars Jean Reno, Gary Oldman and features the film debut of Natalie Portman.
Léon is an Italian hitman (or “cleaner”, as he refers to himself) in New York City's Little Italy working for a mafioso named “Old Tony”.
One day, Léon meets Mathilda Lando, a lonely 12-year-old girl. Mathilda lives with her dysfunctional family in an apartment down the hall, and has stopped attending class at her school for troubled girls. Mathilda's abusive father attracts the ire of corrupt DEA agents, who have been paying him to stash cocaine in his apartment. After they discover he has been stealing the cocaine, DEA agents storm the building, led by sharply dressed drug addict Norman Stansfield. During the raid, Stansfield murders Mathilda's entire family while she is out shopping for groceries. When Mathilda returns, she realizes what has happened just in time to continue down the hall to Léon's apartment; he hesitantly gives her shelter.
Léon: The Professional is to some extent an expansion of an idea in Besson's earlier 1990 film, La Femme Nikita.
Léon: The Professional was released in France on 14 September 1994. The film was a commercial success, grossing over $45 million worldwide on a $16 million budget.