Annie Collins emerged from the wreckage of the last invasion of Sorrow Falls with a spaceship in her garden, a loud alien idea in her head, and-because returning to college was out of the question-a lot of free time.

What she chose to do with the idea, the spaceship, and all that free time, kickstarted a worldwide technological boom. Now, nine years later, it seems as if not a day passes without the announcement of a new breakthrough in something, be it quantum computing, nuclear energy, neurobiology, or some other esoteric corner of cutting-edge science.

The world is in the middle of a revolution of ideas, and the best part? Hardly anyone knows Annie's involved at all.

Yes, everything seems to be working out just great...until the day another spaceship shows up in Sorrow Falls.

This new visitor seems just like the one buried in Annie's garden: same design, same matte black hull, sitting in the same spot in the same empty field. But there are important differences.

For starters, if it's truly a spaceship at all, it didn't come from space; it just... appeared. Also, this one didn't arrive alone. On the same day Sorrow Falls acquired a new spaceship, identical versions manifested in over a dozen locations across the world. All of them just sitting there, not doing anything.

At first.

Who sent these new ships? Why did they send them? What do they want? Annie-with Ed, and Violet, and the rest of the Sorrow Falls survivors-are going to have to figure that out, and fast. Because this time around, they don't have three years to work with; they barely have three months before the end of the world.

Graffiti on the Wall of the Universe is the exciting follow-up to The Spaceship Next Door and The Frequency of Aliens.