When the Berlin Wall went up, Gerta, her mother, and her brother Fritz are trapped on the eastern side where they were living, while her father, and her other brother Dominic are in the West--four years later, now twelve, Gerta sees her father on a viewing platform on the western side and realizes he wants her to risk her life trying to tunnel to freedom.

Marta is a young girl who saw thirty miles of barbed wire appear across her city overnight, separating Berlin into West and East - with Marta's home on the Communist Bloc-controlled Eastern side. Then, just a month ago, Marta's brother became a victim of schiessbefehl, the standing order to fire upon anyone who dared pass into the West. With her family and nation both fractured, Marta will soon be faced with a promising - but dangerous - opportunity....

Summoned by the Queen of England to save the world once again, trusty kid spy Mac B. navigates secret tunnels beneath the Berlin Wall to retrieve cheat codes from an adversarial scientist only to find himself trapped in East Germany.