This is the fourth book in the bestselling Power of Five series, by one of children's most renowned writers. The Old Ones have come to take over the world, and if not, destroy it. There are five children who were born to stop them; Matt Freeman, Jamie and Scott Tyler, Pedro and Scarlett (Scar) Adams, who the story follows. Scarlett is an ordinary girl, who goes to an ordinary high school. But when she goes on a school trip, goes through a mysterious door, she realises who she is. The five Gatekeepers, have a dreamworld, where they all go when they sleep. Scarlett has been having the dreams. But in the last book, the four other children failed to keep the Old Ones imprisoned. They are out there. And they want Scarlett, for if the Five come together, they can destroy the Old Ones. The Old Ones try to keep Scarlett away from the others, by transporting her to Hong Kong, where she gets involved in a shadowy organisation called Nightrise. The Old Ones plan to make Hong Kong into a city of the dead, a Necropolis. Each of the five have powers. Can Scarlett realise hers before the Old Ones destroy the city forever? An amazing book; I finished it in just three days! The writing pulls you into the heart of the story, and I hope that Horowitz will keep writing, so I can keep reading!