According to English literature

In English literature we come across many characters who are treacherous. At first we may think they are honest and sincere. Sooner or later we are forced to change our estimate of    their character. After listening to the words uttered by the ghost of his father (Act I, Scene V), Hamlet comes to the conclusion that a damned villain may hoodwink and deceive others by smiling and smiling. He says “At last I’m sure it may be so in Denmark”.

Hamlet is stupefied by the horrible treachery shown by Claudius, his uncle. How can Duncan think that his ‘loyal’ subject and kinsman Macbeth who has been made the Thane of Cawdor will murder him? Lady Macbeth, to quote Charles Lamb, knows the art of covering treacherous purposes with smiles. She tells her husband to-look like the innocent flower, but be the serpent under it. (Act, I, Scene V).