The first in the Undertakers series.
Will is startled and extremely disgusted when he leaves his house one morning and stumbles upon his neighbor, Mr. Pratt. A very dead Mr. Pratt. Who is still walking around and talking, only Will can also hear his voice in his head. Will runs as fast as he can to get to the bus and away from what he assumes is a hallucination (a bad Pop-Tart perhaps?).
However, when he gets to school he's met with even more undead people. His math teacher. The assistant principal. A couple of janitors. He tries to control his panic, but it's hard. And they seem to realize he can see them. When they attack, Will tries to fight back and luckily is saved by Helene, a cute girl in his class. She fights them off and they escape. Helene tries to explain to Will what's happened, but they're followed everywhere by what she calls Corpses. Soon he's taken to Haven and the whole thing seems unreal. Apparently these beings have come to earth and inhabit dead bodies--but they can animate them for a time. And Will's father is the only adult anyone knows of that could see them for what they are. Which makes Will a big target for the Corpses--they want to study him. And kill the rest.
So...you might have some reluctant readers hesitate to pick up this book. It is pretty thick. The story moves fast for the most part--it could have used a little more editing before printing, but that seems to be the norm now. There is A LOT that goes on, even for the numerous pages. However, it was worth the reading. It's a good story with action, adventure, friendship, and discovering oneself. Not to mention alien beings invading dead bodies.