Liv Varanakis doesn’t like to think about her father much, which makes sense—he fled to Greece when she was only eight, leaving her with just a few painful memories of their shared love for the lost city of Atlantis. So when teenage Liv suddenly receives a postcard from her father, who explains that National Geographic is supporting a documentary about his theories on Atlantis—and asks if she will fly out to Greece and help—Liv is less than thrilled.