When Jeremy's family meets a family from out in the wilderness, it looks like it's going to be the same old story. The outsiders' kid, Valda, acts like Jeremy is a helpless little baby. Sure, he's never caught a fish or fought a hostile mob, and maybe school only lets him read about crafting and never try it himself. That doesn't mean Valda has to be so rude!

But that's not the only trouble Valda's family has brought with them. They share a terrifying story: A new kind of zombie has appeared, one that can do things no zombie should be able to do--steal resources and work together to terrorize the folks who live outside The City's walls.

To stop them, Jeremy and Valda will need to put aside their differences, team up, and learn from each other's cultures--or the Overworld may never be the same!