When Beijing, China, vanishes under a mysterious mushroom cloud, Hunter knows where to seek MC 5. He takes his team back to the court of Kublai Khan in the time of Marco Polo's famous journey to Cathay. This time, their historian is Marcia Lew, a knowledgeable but pedantic authority on Kublai Khan's rule whom Steve can barely tolerate. They must not only capture MC 5 and return him to their own time through their time-travel device to prevent him from exploding, but also prevent him from reaching the ear of the benevolent Emperor -- and persuading him to make changes in his rule that could alter the course of history.
Their search takes them to the Great Wall of China north of Beijing, where they meet with rough and rowdy Mongol guards in the service of the Emperor.
When the team meets with Marco Polo, they must also make sure that they reveal nothing new that he can include in the book that will someday make his name virtually immortal.
During their efforts, Dr. Nystrom kidnaps Jane and takes her to another time!