In an apocalyptic U.S., the rich have abandoned the mainland and choose to live instead on hedonistic cruise ships. Gabby, an aspiring rockstar, signs up to live and work on these cruise ships, but grows disillusioned and escapes on a lifeboat. Her boat is rescued by Bay, a reclusive island-dwelling woman who is used to seeing the dead bodies of ship-jumpers wash ashore. Grudgingly, the lonely Bay accepts Gabby as a friend, and the two women make plans to escape the island together while slowly revealing stories from their pasts.