The Mysterious Bookshop

Higson, Charlie, The Fallen, Book 5

First the sickness rotted the adults' minds. Then their bodies. Now they stalk the streets of London, hunting human flesh.
The Holloway crew are survivors. They've fought their way across the city and made it to the Natural History Museum alive--just barely. But their fight will never end while the Enemy lives, unless there's another way. . . .
The kids at the museum are looking for a cure. All they need are medical supplies.To get them they must venture down unfamiliar streets, where it isn't only crazed, hungry sickos who lurk in the shadows.
In this fifth terrifying entry in Charlie Higson's Enemy series, suddenly it's not so clear who--or what--the enemy is.