Leon is a professional assasin (Jean Reno), who calls himself 'a cleaner.' With employer Tony (Danny Aiello) as his only friend, Leon keeps mostly to himself and his beloved plant.

When circumstances leave 12-year old Matilda (Natalie Portman) in his care, Leon discovers there's more to life than living alone. Together, they make a formidable team against a corrupt cop, Norman (Gary Oldman).

This marks Luc Besson's biggest directorial success in the United States. Besson's credits include Nikita, The Big Blue, and The Fifth Element.