Margo: Wait, so you’re saying Martin tried and screwed up or whatever.
Plover: He was thwarted by someone heroic who knew what he could become. Martin’s own brother Rupert. Rupert Sebastian Chatwin.
Fen: Oh my gods. What a twist. You’re such a natural at this.
Plover: He realized that the only way to stop his brother was sacrifice, so he tied himself to the conduit before his brother could. When Martin discovered what had happened, he was furious. He couldn’t kill his own brother, but he could curse him with eternal sleep. All the people of Fillory thought he was dead.
Fen: What happened?
Plover: You happened. You brought surges of magic so huge you woke Rupert up, and he brought the Takers, and then when he held them at bay, the Fillorians in gratitude made him High King.
Fen: But why did he do all that?
Margo: Yeah. If he was so good why did he become so evil?
Plover: Because while he slumbered he lost the one thing he cared about: the man he loved.