"Jake and Atticus's father, Mark Rosenbloom, is a brilliant archaeologist, but he had no idea that his wife, Astrid, was secretly a Guardian. At least, that's what Astrid believed. The Cahills in the command center aren't so sure. They suspect that Mark might know more than he lets on. Why else would an unidentified source follow Mark around the world, taking sneaky photos of his family? And no, it's not just because he has great taste in hats."