When they were boys, Sam and Dean Winchester lost their mother to a mysterious and demonic supernatural force. Subsequently, their father raised them to be soldiers. He taught them about the paranormal evil that lives in the dark corners and on the back roads of America ... and he taught them how to kill it. Now, the Winchester brothers crisscross the country in their '67 Chevy Impala, battling every kind of supernatural threat they encounter along the way.

When Emery was 6 years old, an alien spacecraft crash-landed in her small town. Whether they came in peace or with more sinister intentions didn't matter: a fierce battle erupted as humans fought for control over their new rivals, an alien species called the Atrians. In the midst of the conflict, Roman, a 6-year-old Atrian boy, found his way to a shed behind Emery's house, where she temporarily protected him from harm, bringing him food, comfort - and friendship. Ten years later, the Atrians have been acclimated to life on Earth, but they are interned in a heavily-guarded camp known as the Sector to keep them separate from humans. Now, for the first time, a group of Atrian teens will enroll in a suburban human high school, with the goal of testing the feasibility of human/alien integration. Emery and Roman find each other again in a school and a society that distrusts everything about the Atrians. While the world around them rages with anger and prejudice, their bond becomes increasingly strong and increasingly dangerous.

A retired FBI serial-profiler joins the mysterious Millennium Group, a team of underground ex-law enforcement experts dedicated to fighting against the ever-growing forces of evil and darkness in the world.