Polanski's film version;

The implication of this action might be that maybe Fleance went to the witches to get information to see what they would tell him. Also maybe he wants to become king, so he going to see what they got to say about Malcoms future, and whats going to happen next. I think he doesnt exactly what to say why Fleance really went over there because he wants to keep the people curious as to what was really going to go down. I also think that if the witches lied to Macbeth they most likely will do the same to Fleance. In my honest opinion I feel as though the witches are up to nothing but bad things. Shakespere wanted to leave the people with wonder, he wanted to leave a good ending. It changes it just a little because he had different endings in the book.