King claudius and queen gertrude are talking to hamlet's old friends, rosencrantz and guildenstern about hamlet's transformation. they hope two of hamlet's friends could discover the cause behind hamlet's continuing depression or at least cheer him up. then polonius enters, telling the king that the ambassador from norway has returned. besides, he has found the source of hamlet's lunacy. the two ambassadors report the domestic situation in norway. later, polonius declares that the prince is mad with love for ophelia and shows the letter from hamlet. he then states that he wants to test his theory. knowing that hamlet often walks alone in the halls of the castle, he devises a plan where he could hide behind the curtain as ophelia talks to hamlet. then, polonius encounters hamlet. he attempts to talk to hamlet, but hamlet's responses seem to be very strange. polonius leaves, and hamlet meets with rosencrantz and guildenstern. he detects that the king and the queen order them to visit him. they soon confess, and tell hamlet that an acting crew has come to the castle, visiting hamlet. hamlet then requests one of the actors to perform a monologue. he declares that the murder of gonzago will be performed the next night.