Like many people, when I think of rats, I think of fleas, filth, and the plague.
Imagine if you will, a world where rats do not carry disease, but cure it. Where instead of killing rats as pests they must be preserved because their blood has the power to heal. When these rats go missing from the lab, it first seems that they may have been stolen. But as the body count goes higher, it's clear these rats have had enough of being experimented on. After a while the rat attacks did get a bit repetitive for my taste but I did still enjoy the story.
I don't usually get into books about government experiments gone awry, but this had a good Sci-Fi/horror/creature feature vibe to it that held my interest.

I received a complimentary copy for review.