While Marj is helping urban archeologists, she discovers a secret map that she has to hide from the authorities. It tells of an underground system of tunnels that cross through mazes of paths under North America, using old limestone caves and aquifers, even connecting to the old ICBM missle bases. It had been a long and brutal war. At the end, one side was banished underground, long decades ago. If this was true, the war may not be as over as they...