The Royals: Masters of War #4

As 1943 wears on, the war slides toward defeat for the Allies, and Hitler's spy in London is a major reason for that. But a minor German Royal has promised the British that he will reveal the identity of the Nazi agent if they can rescue him from the war-ravaged city of Stalingrad. Prince Henry and Princess Rose are sent to hell on earth to retrieve this Prince Oscar of the Royal House of Hanover. But there are far more terrifying things hiding in the Russian rubble than enemy soldiers...