In the begging of the novel (Act 1, scene 1), Bernardo, Marcellus, and Horatio are on look- out duty. Marcellus and Berardo are trying to convince Horatio of them seeing a ghost exactly like the deceased king. Horatio does not believe them until it appears in armour. They think it is a bad omen and a sign of war with Denmark. While they attempt to speak to it, the ghost does not respond. The three character's then decide to tell Hamlet. In the begging of the movie, the scene is of the late king's funeral. People are gathered around his coffin, Gertrude can be seen crying and the uncle lays his sword down. Hamlet is present and shortly leaves after. It's unclear as to why the director chose to add his own scene instead of the original opening, however, it leads me to believe it gives more insight and clarity on the situation.