The quote authored by marcellus is used to describe corruption or a situation in which something is wrong is: "Something is rotten in the state of Denmark."
This quote is often used to describe a situation where corruption or something morally wrong is occurring. It reflects a sense of unease and suggests that there is a fundamental problem or corruption in the political or social order.
This line, spoken by Marcellus in Act 1, Scene 4, refers to the uneasy feeling he has after encountering the ghost of the King, and is often interpreted as a foreshadowing of the corrupt and murderous deeds that are revealed later in the play.