Eric Albright is a luckless slacker willing to let his life just drift by…until the day a small red door appears on the graffiti-covered wall of the railway bridge near his flat, and a gang of strange-looking people dash out of the door and rob the nearby newsagent. From that day on, Eric and his sometimes friend, Stuart Casey, wait for the door to reappear. When it does, they choose to go through…to a place where a mountain-sized dragon with the powers of a god lies sleeping beneath a great white castle.