Dr. Marbles is captured by Hacker and taken to Castleblanca, a Cyberspace version of Transylvania. Hacker’s goal is to transfer Dr. Marbles’ brain power into his newly built robot named Megabyte. Summoned by Motherboard, the kids and Digit arrive with the knowledge that Hacker has taken Dr. Marbles to a castle. There are hundreds and hundreds of castles in Castleblanca. To find Dr. Marbles, the kids must master the art of properly collecting data, organizing it, and graphing the results. Part of the "Cyberchase" series.