The King Must Die - Mary Renault

Theseus is the grandson of the King of Troizen, but his paternity is shrouded in mystery - can he really be the son of the god Poseidon? When he discovers his father's sword beneath a rock, his mother must reveal his true identity: Theseus is the son of Aegeus, King of Athens, and is his only heir. So begins Theseus's perilous journey to his father's palace to claim his birthright, escaping bandits and ritual king sacrifice in Eleusis, to slaying the Minotaur in Crete. Renault reimagines the Theseus myth, creating an original, exciting story.