In Greek mythology, Perseus (US: , UK: ; Greek: Περσεύς, translit. Perseús) is the legendary founder of the Perseid dynasty. He was, alongside Cadmus and Bellerophon, the greatest Greek hero and slayer of monsters before the days of Heracles. He beheaded the Gorgon Medusa for Polydectes and saved Andromeda from the sea monster Cetus. He was the son of Zeus and the mortal Danaë, as well as the half-brother and great-grandfather of Heracles (as they were both children of Zeus, and Heracles's mother was descended from Perseus). Etymology.
https://en.wikipedia.org/wiki/Perseus