Cassandra

Trojan Cassandra, daughter of Priam and Hecuba, was amorously pursued by the god Apollo. Having at first agreed to succumb to his advances, she was awarded the gift of prophecy, but later, when she changed her mind and refused him, Apollo punished her. She would remain a prophetess, but would never be believed. Cassandra's predictions were invariably of disaster, foretelling the murder of Agamemnon by Clytemnestra or the destruction of Troy through the ruse of the Wooden Horse. A Cassandra today is anyone who utters dire warnings of the future, regardless of their truth.