Alex is ready to throw in the towel on their search for Dad, but not Cleo. She decides that visiting the ancient Oracle at Delphi could help, but instead of a mere visit to the oracle, she becomes the oracle, and her change in behavior (talking to Alex whom others can't see) disturbs the job security of her sanctimonious priests. Foreseeing that the priests will take her to her death means only one thing to the priests - time to get a new oracle.
—statmanjeff