In order to test the Ghost's sincerity, Hamlet enlists the help of a troupe of players who perform a play called The Murder of Gonzago to which Hamlet has added scenes that recreate the murder the Ghost described. Hamlet calls the revised play The Mousetrap, and the ploy proves a success. As Hamlet had hoped, Claudius' reaction to the staged murder reveals the King to be conscience-stricken. Claudius leaves the room because he cannot breathe, and his vision is dimmed for want of light. Convinced now that Claudius is a villain, Hamlet resolves to kill him. But, as Hamlet observes, "conscience doth make cowards of us all."
In his continued reluctance to dispatch Claudius, Hamlet actually causes six ancillary deaths. The first death belongs to Polonius, whom Hamlet stabs through a wallhanging as the old man spies on Hamlet and Gertrude in the Queen's private chamber. Claudius punishes Hamlet for Polonius' death by exiling him to England. He has brought Hamlet's school chums Rosencrantz and Guildenstern to Denmark from Germany to spy on his nephew, and now he instructs them to deliver Hamlet into the English king's hands for execution. Hamlet discovers the plot and arranges for the hanging of Rosencrantz and Guildenstern instead. Ophelia, distraught over her father's death and Hamlet's behavior, drowns while singing sad love songs bemoaning the fate of a spurned lover. Her brother, Laertes, falls next.
Laertes, returned to Denmark from France to avenge his father's death, witnesses Ophelia's descent into madness. After her funeral, where he and Hamlet come to blows over which of them loved Ophelia best, Laertes vows to punish Hamlet for her death as well.
