System Crash — Michael Coleman

A blackmail threat has been posted on the Net. Is it a hoax? Or will famous theme-park rides really start to become death traps? As they head off on their theme-park vacation, Josh, Tamsyn, and Rob hope it's a hoax. But a frightening incident proves it's not. With the help of their friends on the Net, they must find the unknown blackmailer--before someone gets killed....