Raven's gate

Blurb

Raven's Gate is the first book in The Power of Five series, written by Anthony Horowitz. It was published and released in the United Kingdom on 1 August 2005, by Walker Books Ltd and in the United States by Scholastic Press under the adjusted series title The Gatekeepers. It is followed by Evil Star, released in 2006, Nightrise in 2007, and Necropolis in 2008, with the final book Oblivion in 2012.
A graphic novel adaptation, written for Walker Books by UK writer Tony Lee and drawn by artist Dom Reardon was released on 3 August 2010.