Who knows that rosencrantz and guildenstern are spies

Hamlet knows that they are spies.

Rosencrantz and Guildenstern are characters in William Shakespeare's catastrophe Hamlet. They are youth companions of Hamlet, summoned by King Claudius to occupy the sovereign from his obvious frenzy and if conceivable to find out the reason for it. 

•as parts of ceremonies and often to ask for peace and blessings from evil. • late at night to entertain themselves or foreign visitors at the camp. • on long journeys through the arizona desert, to keep their energy and minds boosted. • during the long winter nights, when they were cold and the land was not suitable for farming.