Theatre has always staged acts of cruelty. From antiquity until today, audiences have been made witness to gruesome deeds as well as societal taboos. Greek philosopher Aristotle saw this confrontation with the terrifying capable of causing pity and fear in the audience and, thus, of producing a relieving experience, or, a catharsis. French playwright Antonin Artaud also regarded it a necessity for theatre to relentlessly confront its audience with their unconscious fears and desires in order to achieve a cleansing and transforming effect. Many playwrights have since taken up this notion of theatre as a cathartic spectacle and have uncompromisingly exposed their audiences to acts of cruelty. In this thesis I investigate the diverse forms of cruelty that are implemented in Sarah Kanes Cleansed (1998), Harold Pinters The Hothouse (1980) and Martin McDonaghs The Pillowman (2003) and attempt to explore their manifestations, their origins and their relation to the world at large. In Cleansed, the macrocosm of physical, real life cruelty echoes the microcosm of inner, genuinely individual turmoil and mayhem. In The Hothouse, physical cruelty is generated by verbal cruelty that lurks in every dialogue, in officialese and bureaucracy and is a critique of oppressive state systems. The Pillowman employs cruelty as a means to celebrate the art of storytelling as a human capacity and necessity as well as to question the link between creator and creation. All plays depict worlds full of cruelties, directed towards others, towards the self or conjured up in ones imagination. All plays feature cruelties happening in everyday lives and thus have a high pertinence regarding the politics and society of the present. Yet, all plays also tell a story of love, compassion and beauty that withstands the cruelties of the world or how a world would look like that is devoid of them.