Sci-fi book. Overworld and underworld (run by a man who's secretly an alien experimenting on psychic rats to create a rat superrace, lives in a tower). Read around 2010.

[Linliny]

I read this book when I was pretty young, so my memory's hazy, but there's an overworld and an underworld. The underworld is run by rats and a man who's secretly an alien. He's trying to create a rat superrace. Some rats are psychic and have superpowers. The alien lives in a tower. That's pretty much all I remember, but it was very bizarre and the idea of it stuck with me. I read it in around 2010, but I think it was an older book.

Any help is appreciated!!!

[Kris]

Linliny, is this book for teens or adults?

How are the overworld and underworld different?

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