court, Hamlet closely studies Claudius to see his reaction.

The short presentation involves a King and Queen who marry hastily after a murderer pours poison in the ear of the Queen's husband, the rightful king. Of course Claudius bolts from the room quite upset, and Hamlet and Horation know that they have caught the guilty mouse in their trap.

It is extremely important to Hamlet to know for sure whether Claudius is in fact the murderer of his father before Hamlet takes his vengeance. Much of Hamlet's indecision has come because he is not 100% sure of the murderer's identity. He doesn't trust his own instincts and needs conclusive proof.

(This is similar to Dexter, if you watch Showtime. Dexter will only murder serial killers who he knows without doubt are guilty of their crimes and have escaped punishment by the law.)

In act 2, scene 2 of William Shakespeare's Hamlet, Hamlet decides that the best way to test the truth of the ghost of his father's accusation against Hamlet's uncle Claudius—that Claudius murdered Hamlet's father— is to present a play and observe Claudius's reaction to it. Hamlet has heard that guilty people watching a play have been prompted to confess their wrongdoing (2.2.583–587). Hamlet believes that the play best suited to produce this effect in Claudius is an old Italian play called The Murder of Gonzago, and he asks the actors who have recently come to Elsinore Castle to perform the play for the court (2.2.530–531). This play is known as the "play-within-a-play" in Hamlet.

Shakespeare's play-within-a-play of The Murder ofGonzago is based in part on a court document which describes the murder of Francesco Maria I della Rovere, Duke of Urbino, Italy, which occurred in 1538. The document also contains a letter written by Luigi Gonzago, who was the Duke's barber when the Duke was in Mantua, in which Gonzago protests his innocence of the murder of the Duke.

An actual play of The Murder of Gonzago which Hamlet asks the players to perform at court doesn't exist. Shakespeare simply devised The Murder of Gonzago based on the court document's description of the murder of Francesco Maria I della Rovere, and inserted the play into act 3, scene 2 of Hamlet.

There are a number of parallels between the Duke's death in the court document and the play-within-a-play which Shakespeare titled The Murder of Gonzago, and between the court document and the murder of Hamlet's father.

For example, the murderer in both plays is closely related to the victim. Duke Francesco Maria I della Rovere was murdered by his wife's cousin, Luigi Gonzago, and Hamlet's father was murdered by his own brother, Claudius. Shakespeare changes the name of the Player King in the play-within-a-play from della Rovere to Gonzago:

HAMLET. Gonzago is the Duke's
name; his wife, Baptista. (3.2.228–229)

In the play-within-a-play, the Player King says that he and the Player Queen have been married for thirty years (3.2.144-149), which is the same length of time that Duke Francesco della Rovere was married to his wife when he was murdered, and about the same length of time that Hamlet's father and mother, Gertrude, were married, according to the Gravedigger (5.1.140, 143–144).

Hamlet's father was a famous soldier, as was Duke Francesco della Rovere, and they both had many victories. Notable among old Hamlet's victories is his defeat of King Fortinbras of Norway. This is the reason that Young Fortinbras is menacing Denmark at the beginning of Hamlet (1.2.17-25), and trying to regain lands that his father lost to old Hamlet.

Shakespeare might also have been familiar with a portrait of Duke Francesco della Rovere painted by Titian just before the Duke's death. The Duke—full-bearded and looking fierce, if not a little world-weary—is portrayed in full armor. In act 1, scene 2, Horatio describes the ghost to Hamlet much as the Duke appears in the painting:

HORATIO. A figure like your father,
Armed at point exactly, cap-à-pie [meaning head to foot]. (1.2.207-208)

According to Horatio, the ghost also carries a truncheon (1.2.212), as does Duke Francesco della Rovere in the painting, and the Duke's helmet is in the background, with the visor open. Horatio says of the ghost, "He wore his beaver [meaning visor] up" (1.2.243), so Horatio was able to see the ghost's face and recognize it as Hamlet's father.

The most significant parallel among the deaths of Duke Francesco della Rovere, the Player King in the play-within-a-play, and Hamlet's father is that they were all murdered by having a poison liquid poured into one of their ears, which is a unique method of poisoning.

In his letter in the court document, Luigi Gonzago asserts that he accidentally dropped a poisonous lotion into the Duke's ear while he was cleaning it, but he was nevertheless convicted of the murder.

In any event, the performance of the play-within-a-play causes Claudius to implicate himself in the murder of Hamlet's father by suddenly rising and exiting the room, which confirms the ghost's accusations and Hamlet's suspicions.

Hamlet is concerned to discover whether Claudius really murdered the late King Hamlet or if the ghost making that claim was sent by Satan to lure Hamlet into murdering an innocent man. Having rejected suicide as a way out of this dilemma, Hamlet seizes on the traveling players (actors) when they arrive at the castle as a solution.

Hamlet wants them to perform the play "The Murder of Gonzago," which he edits to include new elements, such as a pantomime of the murder of King Hamlet as the ghost described it. Hamlet wants to observe Claudius closely and for Horatio to do the same. Hamlet is hoping Claudius will react in a way that confirms that he is (or isn't) the murderer. Hamlet renames this play "The Mousetrap" because, with the "bait" of the play, he hopes to trick Claudius into revealing his guilt. "The Mousetrap" is referred to as a play-within-a-play because it is enacted within the framework of the larger play, Hamlet, itself.

Ironically, Claudius, who has been worried about the moping Hamlet, is thrilled to see him develop an interest in the players and encourages him to pursue it, not knowing Hamlet's intent.

The "play-within-a-play" is this acting out of "The Murder of Gonzago," or, has Hamlet has renamed it, "The Mousetrap," inside the play by Shakespeare, Hamlet.

In Act 2, Scene 2, Hamlet has just finished grilling Rosencrantz and Guildenstern about their motives. They dissuade him from his anger by pointing out a band of traveling actors who has just made their way onto the grounds of Elsinore.

In a primary example of Hamlet's intellectually quick mind, the prince immediately forms an idea. There is a traditional play that many actors know called "The Murder of Gonzago." This play depicts the murder of a king.

The play's the thing

Wherein I'll catch the conscience of the King (2.2.633-34).

Hamlet pulls one of the actors aside and asks him if he can "modify" the script a little. He asks the players to memorize sixteen lines that he himself will compose and that the players are to incorporate into their act. These lines will reflect the details of Claudius and Gertrude's treachery:

Hamlet eagerly anticipates Claudius' reaction to the scene. He believes that if Claudius reacts negatively (as Hamlet is quite sure he will), that proof of the Ghost's assertions will be validated. Remember, at this point, Hamlet is still wary of trusting the Ghost. It is quite possible that the Ghost may be an evil spirit coming to him in the guise of his beloved father. However, if Hamlet gets the proof he needs, via Claudius' reaction, he will know the Ghost can be trusted.

In act 2, scene 2, an acting troupe arrives and agrees to perform the play The Murder of Gonzago at Hamlet's request. Hamlet also asks the actors if they can perform several lines that he devises. After the actors leave, Hamlet delivers a soliloquy, where he reveals his plan to have the performers reenact his father's murder in the orchard while Claudius is in attendance. Hamlet then mentions his plan to closely analyze Claudius's reaction to the scene in order to ascertain whether he is responsible for assassinating Hamlet's father.

In act 3, scene 2, the actors perform what is referred to as "the mousetrap," and Claudius watches as the players reenact how he murdered his brother, King Hamlet. Claudius suddenly stands up and leaves the theater, which confirms his guilt. The Murder of Gonzago is a play within the play Hamlet. In addition to the performance of The Murder of Gonzago, Hamlet's false behavior and feigned madness correlate to the concept of a "play within a play."

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