Raise a false alarm, as in Helen's always crying wolf about attempted break-ins, but the police can never find any evidence. This term comes from the tale about a young shepherd watching his flock who, lonely and fearful, called for help by shouting "Wolf!" After people came to his aid several times and saw no wolf, they ignored his cries when a wolf actually attacked his sheep. The tale appeared in a translation of Aesop's fables by Roger L'Estrange (1692), and the expression has been applied to any false alarm since the mid-1800s.
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