The phrase is French for the mutants are falling back asleep, and the clip circulates online under that exact title as a short reaction sound. Its origin is not clearly documented, so it is shared mainly for the deadpan delivery and the oddly specific wording rather than a known scene. Creators reuse it in edits, streams and group chats whenever activity fades, treating the line as a mock announcement that whatever was stirring has settled again, which keeps the joke understandable even for viewers who do not speak French.