Tunnels of Blood is the third book in the Cirque Du Freak series. This installment follows young half-vampire Darren Shan as he and his vampire mentor, Mr. Crepsley, leave the Cirque Du Freak for a secret mission. They take along Darren's friend Evra the Snake Boy as a companion for Darren while Mr. Crepsley pursues his mysterious agenda. Through the course of the book, Darren gets a girlfriend and figures out Mr. Crepsley's secret, which puts them all in mortal danger.
This is a decent follow-up to the first two books, but it is not particularly exciting. It definitely leans more toward YA fiction (Does the girl like me? Do I like her? Should I kiss her?) than toward horror. Although it does get fairly interesting near the end, I found it on the whole to be a little dull. It's not a bad book, and would be particularly appropriate for a middle-schooler, but it's not a great piece of stand-alone work.
I am not sure that I'd recommend this -- I am not even sure if I will bother getting the next book in the series. Although there are some threads of the story that I'm really interested in, I don't know if it's really worth my time.