A year after the summer the doors opened, Felix and Moira Valdez come back to Horizon Reach and find a door that shouldn't exist.

It's cold and silver, it has no rhythm, and it ignores every rule the twins learned the hard way. The marker stone can't sense it. Their old methods can't read it. And it may not be opening on its own ? something on the other side might be knocking.

With their friend Jo at their side and their mother finally let in on the family secret, the twins start pulling at the mystery. A corroded twin of their own Anchor turns up with a set of initials carved into it ? initials that point much closer to home than anyone wants. A dealer in town recognizes Moira's coin. And Sable Moreau's network is still circling the property.

One door. Six weeks. And a warning from a future that is trying very hard not to happen.

Book Two of The Horizon Reach Chronicles.