"The boy who cried 'Wolf!'" is a fable by Aesop. The protagonist of the fable is a bored boy shepherd who persists in alarming nearby villagers by calling out 'wolf'. When he is actually confronted by a wolf, the villagers do not believe his cries and his flock perishes. The moral of the fable is that a persistent liar will not be believed, to his or her own loss. It serves as a lesson about how much easier it is to break trust than to build it, and how if someone continually lies, nobody will believe them even when they are telling the truth.
The story is as follows: a shepherd boy, who watched a flock of sheep near a village, brought out the villagers three or four times by crying out, "Wolf! Wolf!" and when his neighbors came to help him, enjoyed a laugh at their expense. A wolf, however, did truly come at last. The Shepherd boy, now really alarmed, shouted in an agony of terror: "Please, do come and help me; the wolf is killing the sheep"; but no one listened to his cries, nor rendered any assistance. The wolf, having no reason to fear, at his leisure killed the whole flock.
"To cry wolf" is to persistently raise the alarm about a non-existent situation, with the implication that the person who cries wolf will not be believed should a real emergency take place.
