The City of a Hundred Spires is still sleeping. It is a beautiful city, and like any other city, it has its own challenges and its own problems. It has its own unique mix of people, with their different cultures, languages, even gods. But it is a free city. It is a city that is content with its lot when it goes to sleep at night.

When it wakes up today, it is going to be to the foreign sounds of a foreign army. It is going to be to the clop of clumsy feet that do not know their way around the city and yet have the audacity to claim it as their own. The first ones to enter the city are the ones on the motorcycles. They ride recklessly through the fresh snow towards Černín Palace, where their Fuhrer will officially claim this city. But they don't know the way. The winding streets confuse them. They do not understand the city.

It is March 15, 1939, and the city is Prague, the capital of erstwhile Czechoslovakia, waking up to the march of German boots on their snow-covered streets. Suddenly, in a city where Czechs, Slovaks, Germans and Jews had been living together as neighbours and friends for centuries; they are now being segregated. Overnight, people's family trees will determine what sort of life they will lead, or if they live at all.

Ester and Klara Barsch, daughters of Joseph Barsch, owner of a chemicals factory, are two of the lucky women whose life does not change much. That is because they are of clear German descent, proven by their family tree. But a lot of their friends are not so lucky. Several will lose their lives in the coming days, months and years simply because of their faith, their views, opinions or even for knowing the wrong person. Their Jewish friends will all be lost, either driven into ghettos or, if lucky, emigrated.

Nothing is the same after that fateful March day. The Germans take over control of the city with the ruthless efficiency that they are known for. The expensive glassware in the boutiques along High Street are gone; replaced by shops with broken windows, or windows with crude banners claiming them to be German. Even the proud statue of the Iron Man on Platnéřská Street no longer looks proud.

In the dreadful years that follow, Fiegl, Ester and Klara have seen it all. Jews driven into living in ghettos, or moved to Terezín, only to disappear forever. The Czechs reduced into a labour force forced to work 60 hour weeks to support the German war machine. Anyone speaking out against German policy dies a quick, but not merciful death.

But the people are resilient. And they are determined to oppose this tyranny, in every way they can. They have formed a network, the Tři králové (The Three Kings). It is led by three ex-military officers. But Josef Mašín and Josef Balabán are already dead. Only Václav Morávek remains. And Fiegl, Ester and Klara are trying to help in any way they can. Little do they know that in just a few short years, they will find themselves in the middle of one of the most daring conspiracies of their time. It will be a long and treacherous journey.