Hamlet denounces his mother's marriage to his uncle by calling her weak since she is a woman.
Frailty, thy name is woman!
After he is told that his father's ghost was seen, Hamlet seeks out to find it. When he finds the ghost, it tells him that his uncle, now step-father, murdered him in order to become King.
Thus I was sleeping, by a brother's hand of life, of crown and queen, at once dispatched
Claudius becomes suspicious of Hamlet and asks his friends, Rosencrantz and Gildenstern to keep an eye on him for any unusual behavior.
I entreat you both...to draw him on to pleasures and to gather, so much as from occasion you may glean, whether aught, to us unknown, afflicts him thus that, opened, lies within our remedy.
Go thee to a nunnery, go, farewell. Or if thou must marry, marry a fool, for wise men know well enough what monsters you make of them.
Claudius and his chief advisor, Polonius, eavesdrop on Hamlet and Ophelia, Hamlet's lover. They hear him reject her.
A play is performed in front of the castle portraying a story close to Hamlet's father's ghost's story Claudius murdering him. Claudius immediately stops the play, which makes Hamlet think he's guilty, and he makes a plan to kill him.
Now could I drink hot blood, And do such bitterness as the day, Would quake to look on.
O, my offense is rank, it smells to heaven. It hat the primal eldest curse upon't, A brother's murder.
Claudius arranges for Hamlet to be banished to England. Then, he confesses to the murder during prayer and Hamlet overhears, but refuses to kill him then because it's during church.