From the author of the Themis Files and the Take Them to the Stars series comes a new, riveting story of first contact.

What kind of message would you have sent into space?

I wouldn't have.

Why not?

Because they might hear it, and then they might come.

A mysterious radio signal is picked up from a neighboring star system. A group of experts is brought to the floor of the Grand Canyon to investigate its origin and its meaning as the planet suffers one natural disaster after another. Cut off from the rest of the world, they must question everything, including each other, if they hope to solve the mystery.

What they discover could be the difference between life as we know it--and the end of the world.