A lawyer, who represents the German government against the Greek reparation claims for Nazi crimes in World War II, travels to Greece and meets one of the remaining survivors of the Kalavryta massacre that took place in 1943.

Hoping to entrap Maria von Gall, who runs a courageous underground railroad for Jews in France, the Nazis kidnap her son Thomas, a brilliant 11-year-old chess master. An exchange arrangement goes awry and he sees her die in a hail of bullets; but he is rescued by his American father, whom he has never met before, and who plans to flee with him to Spain. However, Queen Maria had solemnly entrusted her little pawn Thomas with a precious secret and a terrifying mission, and it was time for him to move. A pawn may become an important piece by slowly, quietly advancing all the way through the enemy's ranks. Or a pawn may die trying. Retreat is what a pawn can never do.