Director Luc Besson’s 1994 crime thriller The Professional (or Léon to our French readers) introduced audiences to a different kind of hitman movie, as well as one of today’s leading actresses. The film about an orphaned adolescent who is taken in by her friendly neighborhood assassin featured standout performances by its three main stars: Natalie Portman, Gary Oldman, and Jean Reno. And 20 years later it still holds up with Gary Oldman delivering one of the best psychotic roles — and there have been a lot of them — of his entire career.

To mark the film’s 20th anniversary, I’ve dug up some facts on how the movie came together and where young Natalie Portman drew her inspiration from. (Hint: it involves a fictional Aurora, IL celebrity.)

1. The casting director initially thought Natalie Portman was too young. Natalie was at first turned down after her audition because the casting director thought she was too young for the part. She returned to read again, and impressed casting director Todd Thaler into deciding to give the young actress her first part in a movie.

2. Jean Reno decided to play the part as if Léon was a bit slow. Reno knew that for the audience to accept that this girl had been taken in by a trained killer, he would have to make Léon a bit emotionally repressed and child-like. He decided to play the character as if he was a bit mentally slow and allow Matilda to have emotional control of the scenes, so that the audience would realize that his character wasn’t going to take advantage of the girl.

3. Natalie Portman’s parents had strict guidelines for all the smoking scenes. The biggest concern about the film for Natalie’s parents wasn’t the violence, but the character trait of Matilda being a smoker. Her parents drew out a strict contract with director Luc Besson that there would only be five smoking scenes, that Natalie would never be seen inhaling or exhaling from a cigarette, and that her character would quit the bad habit by the end of the movie.

4. A thief turned himself in to extras dressed as police. A robbery went down in the neighborhood where the film was being shot and upon leaving the scene the thief walked into the film set. When he noticed a group of extras in police uniforms standing around, he turned himself in believing them to be real cops.