A spectacular new middle-grade fantasy series from NYT bestselling authors Garth Nix and Sean Williams, in which two twins find that they must act as wards against a threatening evil.

The Evil has been trying to break into our dimension and dominate the earth for centuries. Unbeknown to most of us, there are Wardens all over the globe, who protect humanity from the Evil that asserts itself at the Portals, which are the only places through which the Evil may pass into our world.

Jaide and Jack Shield don't know that the world is under attack. They don't know that their dad and their Grandma X, who they move in with, are Wardens, or that they themselves are troubletwisters, young Wardens just coming into their powers.