Enemy Agent

From BoardGameGeek:

Players divide their 6 travelers into 3 secret agents and 3 tourists and select matching passports that will be used throughout the game. With throws of the dice, the travelers are moved from the hotel or railroad station toward the wall. After passing through the checkpoint, which can cause delays, travelers are moved toward the opponents buildings to locate his "Master Plan". When found, the "Master Plan" is rushed back through a checkpoint or "Over the Wall".In addition, each player has two inspectors, which are used to hunt opposing enemy agents.