The Supernaturalist is a 2004 young adult novel by Irish writer Eoin Colfer, best known for the Artemis Fowl series.
The book take place in a near future dystopia. Our protagonist is one Cosmo Hill, raised in a grim orphanage where the orphans are used as experimental subjects. He escapes the orphanage and almost dies in an accident before being rescued by "The Supernatralists", a crew of people (two teenagers and one mutant adult who is super-intelligent but physically resembles a young child). The purpose of this crew is to hunt "parasites", blue energy creatures who suck the life out of people. They can only be seen by those who have had a near death experience, and Cosmo now qualifies. They set out on a war against the creatures that stretches from the slums to outer space, but as the story progresses, they discover that the parasites are not what they first appear to be.
Eoin Colfer is one of the the top young adult novelists, and this book is certainly a good and original work. Although many of the scenes and settings are standard cyberpunk, he manages to come up with some new ideas and locations. The book also includes some surprising and well-timed plot twists, enough to keep it unpredictable and interesting. The biggest flaw of the book are that despite the conceptual depth, the execution is bound by the conventions of young adult literature: the story has to move quickly and there is more action than character development.
It was also interesting for me that at nine years old, this book is already getting a bit dated. When I started reading it, I didn't know the publication date, and I felt it was somewhat clichéd , although when I found out that it was a decade old, it seemed much more original. But after the success of The Hunger Games, the entire genre of "dystopian young adult" has become overdone in the same way that Twilight ruined "young adult paranormal romance".