Macallan awakes in her grandmother's apartment and realizes she is late to teach her class at Rockefeller University. She rushes to campus but meets a strange doctor along the way that says he is treating Macallan's ailing grandmother. He also claims to have knowledge about Leviathan. But before he can explain, Macallan is kidnapped by four individuals that claim to be immortal. These immortals are part of a community known as Leviathan that desperately need Macallan's help to find something called The Key. When she rushes back to tell her partner James Saltzer what has happened, she makes a horrible discovery.