An educational adventure! Her whole life Cassidy has felt disconnected from her peers, especially after the tragic death of her father. Now, as she prepares to finish middle school and looks forward to the next step in her life, things seem harder than ever. Then, one day, a mysterious substitute teacher appears at her school bearing news. He has a test, it seems. A test that might allow Cassidy admittance to one of the city's more prestigious magnet schools.

But the test is not what it seems. Before long, Cassidy and her best friend Jay, find themselves enrolled in the shadowy "Agency", an organization devoting to making sure that history stays history. Before long, Cassidy and Jay find themselves passing back through time to ancient Egypt. Their mission is to save Rameses the Great at the Battle of Kadesh. Things, however, turn out to be more complicated than they thought. Quickly, Cassidy and Jay find themselves embroiled in palace intrigue and learn that a mysterious conspiracy led by "Pa-Neck" (the serpent) is working to keep Rameses from even traveling to the battle.

Cassidy and Jay work feverishly. But, before long, it becomes clear that unraveling the mystery of who is "Pa-Neck" and stopping him will require every ounce of their skill and ingenuity.