There are several themes intertwined in Shakespeare’s Hamlet but perhaps most prevalent is that of revenge. It is the focus of three important characters; Fortinbras, Laertes and Hamlet himself, all of whom seek to avenge the deaths of their fathers. Throughout the play revenge is a dominant theme that envelops Hamlet and sometimes causes him to act irrationally, such as when he stabs and kills Polonius through a curtain purely through instinct based on a chance that the unseen character may be Claudius. Many critics have suggested that Hamlet is an opportunist and his murder of Polonius supports this. However, this opportunist thinking is brought about by the bloodthirsty notion of revenge which is most definitely the main theme of the play. Unfortunately this revenge blinds Hamlet and ultimately leads him to commit sins which in turn lead not only to his own death but also the death of his family, the woman he loves and the loss of the Danish throne to Norwegian hands.
The first sense of revenge in the play is introduced through the ghost of Hamlet's murdered father, whose message to his son cries for vengeance against Claudius, now King of Denmark, for murdering him and marrying his Queen; “Ghost: The serpent that did sting thy father’s life now wears his crown. Hamlet: O my prophetic soul! My uncle? Ghost: Ay, that incestuous, that adulterate beast.” From this early stage the theme of revenge motivates Hamlet and at that moment he appears prepared to kill Claudius in cold blood where he stands. However, as time progresses Hamlet takes little to no action and the audience may begin to doubt whether he can really fulfil his role as the glorious revenger he originally aspired to be and from this we may question how motivational revenge truly is. It is not until Hamlet witnesses the players (actors) in court that he seizes the opportunity to confirm Claudius’ guilt to himself. This is not surprising when we consider that Elizabethan attitudes to the supernatural were very negative and might perceive the ghost to be a sinful subject of Satan and therefore a Shakespearian audience are likely to have approached the ghost of Old Hamlet with caution and might forgive Hamlet’s delayed sense of revenge as a result. However, presented with the opportunity to confirm Claudius’ guilt for himself Hamlet hastily hatches a plan to present a play mirroring the actions that Claudius apparently took against his father (“The Murder of Gonzago” which he also refers to as ‘The Mouse Trap’). The play within the play is a significant milestone in clearing Hamlet’s mind on his path to be a true revenger. He slyly unnerves Claudius prior to the play, hinting that he knows Claudius has every reason to feel awkward and guilty presented with this play; “’tis a knavish piece of work, but what o’ that? Your majesty and we that have free souls, it touches us not.”