Leon (aka The Professional) is moving into my "all time favourites" list. It was damn impressive the very first time I saw it (going in totally blind, without knowing a thing about what the movie was about, I was blown away), but I'm finding it has real rewatchability.
Strange though - I always forget how effective the opening sequence is - tense, intense, funny, character revealing... and yet not memorable. Perhaps because for me the story really starts when Mathilda is introduced.
Portman convincingly portrayed maturity and nuance, a stellar performance that wasn't repeated until Beautiful Girls years later. I'm looking forward to Closer which is also supposed to be one of her best outings. She is the heart of the movie, without her it couldn't have worked. It'll be interesting to see her in the upcoming V For Vendetta film - there are many similiarities between Mathilda and Evey Hammond. Both are girls forced to grow up before their time as a result of the brutal world in which they live and the intimate association they form with a complex, multi-faceted killer.
Noted: even in the extended edition where she skirts a lot closer to becoming a killer she never actually loses her innocence, ie she never directly kills anyone.
Also noted: Gary Oldman is indeed as hammy as I remember him. Well, I thought he was hammy... little did I know, until The Fifth Element taught me the real limits of a scenery only diet.