Hamlet now feigns insanity to be able to convict Claudius of murder and treason, and takes special delight in making a fool of Polonius, the king's Polish-born councilor. Polonius, convinced of Hamlet's act, is certain that Hamlet's madness stems from his unrequited love for his daughter Ophelia. He forbade his daughter any kind of relationship with Hamlet. So he now fears for his status at court and offers his services to the King in this matter in an attempt to redeem himself before the King of any guilt. Namely, he wants to find out the reason of Hamlet's mad behavior for the King by staging a meeting between Hamlet and Ophelia on which Polonius and Claudius will spy upon. Claudius, perhaps suspecting Hamlet's ruse, also asks Hamlet's schoolmates Rosencrantz and Guildenstern to monitor him, but Hamlet does not let his guard down and sees the intention behind his schoolmates' sudden visit. He enlists a company of traveling performers to stage an existing play which he has modified to re-enact the circumstances of his father's murder.
"The play's the thing Wherein I'll catch the conscience of the King." [Act II, scene II]
Shortly after the play begins, Claudius cannot bear to watch, rises and asks for lights. The king's anguished reaction to the performance (which Horatio also notices) convinces Hamlet of his guilt. Shortly afterwards, Claudius arranges for Hamlet to be deported to the Danish territories of England along with Rosencratz and Guildenstern, where he is to be killed upon arrival. Alone, Claudius privately expresses his disgust at what he has done, and offers a prayer of repentance. Hamlet discovers Claudius at prayer and prepares to kill him, but then stops, reasoning that he does not want his revenge to have the result of sending the repentant Claudius to Heaven. Ironically, after Hamlet slips away, Claudius concludes that he is unable to repent in his current state of mind; thus, if Hamlet had not attempted to arrogate to himself the destiny of Claudius's soul, rather than just his life, he would have gotten the ultimate justice he sought. By trying to go beyond the ghost's orders, he has doomed his efforts to failure.
Hamlet confronts his mother about the murder of his father and her sexual relations with her new husband, and during their conversation, he stabs Polonius, who has been hiding behind a tapestry eavesdropping on their conversation, thinking it may have been Claudius. Unrepentant of his crime, he continues to admonish his mother. King Hamlet's ghost makes a reappearance to rebuke Hamlet. Hamlet's mother cannot see the ghost, and sees him conversing with it, she is convinced that her son has really gone mad.
Claudius, who has figured out Hamlet's real motivation, sends Hamlet to England, supposedly for his safety, but accompanied by a sealed letter to the English ordering his death. Rosencrantz and Guildenstern are sent along to ensure the orders are carried out. On the way to England, Hamlet's ship is attacked by pirates, who take Hamlet prisoner but then return him to Denmark.
Meanwhile, Ophelia loses her sanity, being gravely disturbed by Hamlet's rejection and the death of Polonius. She sings a number of rustic melodies that Shakespeare may have pilfered from the English folk tradition. In what may have been a suicide attempt, she falls into a brook and drowns. Laertes, her brother, returns from overseas, and is hungry to avenge his father's and sister's death.
Hamlet, returning from his voyage, meets Horatio at a graveyard outside Elsinore castle just as Ophelia's funeral cortege arrives there, where a gravedigger (jester/clown) is digging. Hamlet finds the skull of Yorick (see skull as a symbol), an old jester to the court who has carried him on his back during his childhood days, and proclaims, "Here hung those lips that I have kissed I know not how oft." As Hamlet broods on mortality, the cortege arrives with the King, Queen and Laertes. Hamlet is so distraught to learn of Ophelia's death that he leaps into the open grave and grapples with Laertes.
When Laertes and Claudius learn of Hamlet's return to Denmark, they scheme to kill Hamlet with the intention of making the death look like an accident. To this end, Claudius instructs Laertes to challenge Hamlet to a fencing match. In order to encourage Hamlet to accept, Claudius lays stakes on the match which are very disfavorable to himself. Unknownst to Hamlet, Laertes will be fighting with a sharpened and poisoned foil, instead of the customary bated blade. In addition, Claudius prepares some poisoned wine for Hamlet to drink as a toast, just in case Laertes is unable to hit him.
While waiting for the match to begin, Hamlet and Horatio jest with the diffirent fop Osric. At the match Hamlet wins the first two rounds, and Gertrude drinks some of the wine to have a toast on him, unaware that it is poisoned. Hamlet is hit with the sword and fatally poisoned, but in the ensuing brawl, he swaps blades with Laertes, and deals a deep wound to Laertes with the poisoned sword as well. The Queen dies from the wine, and warns Hamlet that the drink is poisoned. With his dying breath, Leartes also confesses the whole plot to Hamlet. Enraged, Hamlet kills Claudius with the poisoned weapon, forcing him also to drink the poisoned wine, at last avenging his father's death.
Horatio, horrified at the turn of events, seizes the poisoned wine and proposes to join his friend in death, but Hamlet wrests the cup away from him. He orders him to tell his story to the world to restore Hamlet's good name. Hamlet also recommends that the Norwegian prince, Fortinbras, be chosen as the successor to the Danish throne. Hamlet dies, and Horatio mourns his passing:
"Now cracks a noble heart: Good night sweet prince: And flights of angels sing thee to thy rest!" [Act V, scene II]
Fortinbras enters with English ambassadors. Shocked by the carnage, he orders a military funeral for Hamlet, whilst Horatio offers to relate the whole tale to him and the public.
