Incarceron by Catherine Fisher

The idea was humane and grand: create a prison that would be like paradise. Once in, however, no one was allowed out. And the prison grew into a conscious being, watching over everything inside itself. Watching the hellish life of the inmates. Outside? There was the Warden, watching over the prisoners and the prison. The Warden watched what happened Outside also. He had grandiose plans for his daughter, Claudia. But Claudia had her own ideas.

This fantasy novel by Welsh author Catherine Fisher describes a complex and fascinating world. Grade 7 - up