Acrisius was Perseus’s grandfather and the king of Argos warned about his grandson. An oracle told Acrisius that Danaë’s son would eventually cause his death.
To prevent the prophecy, Acrisius confined Danaë, but Zeus fathered Perseus with her according to the myth. Acrisius then placed Danaë and the infant Perseus in a chest and cast them into the sea. They survived and reached Seriphos, where Perseus grew up.
Years later, Perseus returned to mainland Greece. He did not intentionally kill Acrisius: during athletic games at Larissa, Perseus accidentally struck his grandfather with a discus. Because he had caused the predicted death, Perseus refused to inherit Argos and instead exchanged kingdoms with Megapenthes, becoming associated with Mycenae. The story illustrates the Greek mythic theme that attempts to escape prophecy can help bring it about.