"The 120 Days of Sodom" is an unfinished novel written by the French philosopher and writer Marquis de Sade in 1785. The story follows four wealthy men who isolate themselves in a remote castle, where they engage in extreme sexual and moral depravity over a period of 120 days. The narrative explores themes of power, cruelty, and the limits of human desire. The work is notorious for its graphic content and controversial subject matter, leading to its censorship and banning in many places. Despite its disturbing themes, "The 120 Days of Sodom" is considered a significant piece of literature that challenges societal norms and examines the darker aspects of human nature.