Book 2 of the Doors into the Dimensions Series Joe and Alice helped the Artificial Intelligence computer of the Barton Street Gym win the battle for Milwaukee. Now the Superstrand Opti-cable network is about to connect Milwaukee to Chicago. What will they find, in the larger city? Has a single computer assimilated the city? Is there an ongoing battle for dominance? Or a really poisonous winner? Not to mention three other groups exploring Chicago Dimension Six. Joe's got his work cut out for him, beating the Chicago Rattlesnake and saving his dad.