This was the pivotal moment from the first GODFATHER film which propelled Michael Corleone into the life he really didn't want. Up till now, Michael was a normal man, just returned from the military and not wanting any part of the family business, the life of the Mafia. However, when his father, played by Marlon Brando, is gunned down, Michael volunteers to be the one to kill Solozzo and a corrupt police officer who had struck Michael at the hospital. The scene itself is a classic sequence of building tension. We know that Michael must excuse himself to go to the bathroom where a gun will be waiting for him. Al Pacino's performance as Michael is brilliant, because on his face you can see the nervousness of having to kill a person for the first time. He returns from the bathroom, sits back down, and waits for his moment. Solozzo talks to him but he's not listening. And on the film's soundtrack, we hear the growing squeals of a train and finally Michael stands up, and shoots Solozzo right in the head. He points the gun to the police officer, hesitates for a moment, and shoots him twice. It's a very grisly scene, and a very pivotal moment for the story, as Michael turns into a completely different person, and by the end of the film, he's the new Don of the Corleone family. Everything that happens in Michael's life in the remainder of the films can all be traced back to this sequence, when this one decision and action changed the entire course of his life.