from the play, a lot of the dialog and soliloquies were rearranged or those that were longer or difficult to understand were cut completely.
A major difference throughout the entire play was that the arrangement and overall dynamics of some scenes are modified.
The most noticeable was Act I, Scene I. In Shakespeare's version, the two watchmen, Bernardo and Marcellus, are joined by Horatio so they can prove to him that the apparition of the recently deceased King Hamlet has been appearing on the watchtower for the past three nights. Horatio had been skeptical in believing them at first, but is proved wrong when the King does indeed appear. In Zefferelli's version, the opening scene begins with Queen Gertrude viewing her dead husband (King Hamlet) just before he is to be buried, followed by Claudius announcing his marriage to Gertrude. There is no mention of the King Hamlet's funeral or Claudius and Gertrude's wedding announcement in the book. Also, in Zefferelli's film version, there is no mention whatsoever of Fortinbras or the war. Since the first scene of the play was eliminated from the movie, there was no conversation to inform us of Denmark preparing for the war against Fortinbras army. Since we do not see the ghost of King Hamlet in the opening scene following the mention of the war, we do not see him in his armor which is symbolizing Denmark preparing for battle in his appearances later in the
movie.
Another major difference between the play and the movie was that Zefferelli embellished much, much more upon the involvement of the Oedipal complex between Hamlet and Gertrude. There is really no actual mention of this attraction in the play, just a slight suggestion of it. It seems that in the play Hamlet is more disgusted with his mother's incest with his uncle than interesting in pursuing an incestuous relationship with her himself. However, in the film, Hamlet appears to be violent in a sexual way towards Gertrude. There are several times throughout the film where Gertrude and Hamlet kiss in a seemingly sexual way, as well as the scene where Hamlet has Gertrude pinned down on the bed mocking her sexual relationship with Claudius and appears to be making some "sexual movements" that are not mentioned in the play.