Shaken by a shocking loss, Amy and Dan flee to an exotic land and trace the footsteps of their most formidable ancestor yet: a military leader of mythic proportions.

"Nora and Ben's younger sister, Birdy, loves to keep secrets. She surprises her family more than once: She hides a kitten in her room. She writes a beautiful poem. One day Birdy watches her mother spit into a tube, ready to send it off to find out more about herself and where her family came from. Birdy spits into a tube, too, when no one sees her. But when the test results come back, there is a surprise. Where did Birdy come from? Nora and Ben must...

Thirteen-year-old Dan Cahill and his older sister, Amy, are the latest guardians of the Clues -- thirty-nine ingredients in a serum that transforms whomever takes it into the most powerful person on earth. They think they've done everything right, but a tiny mistake leads to catastrophe. The serum is missing and Dan and Amy have to get it back and stop who stole it ... before it's game over.

"When 12-year-old Max is sent to live with his eccentric grandfather for the summer, he finds himself on an unlikely quest to uncover an enchanted book that contains the key to defeating an unearthly nemesis"--