Though a goddess, Harmonia and her husband were briefly transformed into snakes in some versions of the myth. Harmonia bequeathed the necklace to her daughter Semele.
Semele wore the necklace on the day her affair with Zeus was discovered by Hera. Hera tricked her into attempting to force Zeus to reveal who he was. This would require showing himself in his full glory; a sight fatal to any mortal. Undeterred by his pleas, Semele saw Zeus as a god and immediately burned to death. Zeus managed to save the unborn child within her.
Semele's sisters Ino, raised her nephew Dionysus and later wed Athamas. A jealous Hera turned Athamas mad and he attempted to kill Ino. She jumped into the ocean where Poseidon, in pity, transformed her into the goddess Leucothea. Another of Semele's sisters; Autonoe, had a son Actaeon, who saw Artemis while bathing and was turned into a deer and torn apart by his own hunting dogs. After Dionysus grew up, he rescued his mother from the Underworld and she became the goddess Thyone.
Laius, Jocasta and Oedipus
The necklace was not worn until a great-grandson of Cadmus; King Laius, gave the jewellery to his wife; Jocasta. It allowed her to retain her beauty and she kept it after her husband was unwittingly killed by their abandoned son Oedipus. She later (ignorant of his identity) married Oedipus and, when she found out, hanged herself. Oedipus also gouged his eyes out. Their children; Antigone, Ismene, Polynices and Eteocles all suffered tragedies of their own.
Polynices, Antigone and Eteocles
The throne was shared by Polynices and Eteocles, alternating rulership yearly. One day, Eteocles refused to give up the throne and banished his brother. Polynices, who inherited the neckalce, gave it to Eriphyle, Queen of Argos, to persuade her husband Amphiarus, to support him in attacking Thebes. Both Polynices and Eteocles were killed in the battle and Creon, brother of Jocasta and now King of Thebes, placed a death penalty on any who buried the Seven.
Antigone, wanting to ease her brother's lost soul, buried him against the warnings of her uncle and sister. She was to burn to death. Ismene, though innocent, wanted to share her sister's burden and said she shared the guilt. Creon's son Haemon, engaged to Antigone, confronted his father and later killed himself out of grief.
Eriphyle and Alcmaeon
Eriphyle received the news of her husband's death and Alcmaeon, one of her sons, blamed her and killed her. He was pursued by the Erinyes to the court of a minor King Phegeus. Phegeus married his daughter to Alcmaeon and received the necklace as a gift. He then ordered his sons to kill Alcmaeon, and puts his daughter into a chest and threw her out to sea.
Amphilochus, fearing the curse of the necklace, approached an oracle for help. The oracle advised him to put the necklace to the temple at Delphi, to avoid hurting more human wearers.