Nightrise: Anthony Horowitz

Book III of The Power Of Five. Teenage twins Scott and Jame have never known who they are or where they came from but they do know they have always possessed extraordinary powers. When Scott is kidnapped by the sinister Nightrise Corporation and Jamie is framed for murder, they must use those powers to survive. But Jamie is flung thousands of years into the past, brought face to face with the full horror of the Old Ones and learns the truth of his heritage...