"Knock" is a popular comedy play written by Eugene Ionesco in 1956. It features a character named Bérenger, who experiences a series of absurd and humorous interactions with a mysterious visitor. The play explores themes of communication, existentialism, and the absurdity of life. The central plot revolves around the arrival of a stranger who repeatedly knocks on a door, leading to a series of increasingly bizarre conversations. The play is known for its minimalist setting and its ability to provoke thought while entertaining the audience with its quirky dialogue and situations.