.While a World War rages in the trenches of Northern France, Sergeant T.S. Crake leads Unit 13, a secret elite military force, deep behind enemy lines. The diverse force follows the rumors and vague reports of diabolical medical experiments back to a small occupied village where the Germans have created something monstrous - an unexpected weapon that will fundamentally change the very nature of modern warfare. When one of their own is captured during their escape, Sgt. Crake must decide whether to risk the rest of the Unit in a daring rescue. Reuniting with the Unit's support team, they are joined by two new powerful allies and the question becomes that much more pressing. Do they return to their temporary base in England or do they follow their friend's trail into the very heart of darkness? Crake ultimately decides he cannot leave a comrade to suffer at the hands of madmen and will risk everything to save his friend. Their journey takes them halfway across Europe to the German's main medical facility - hidden in the ancient Altenschatten Castle. Will they survive the treacherous road into the lion's den? And what will they find when they get there? What horrors are lurking in the shadows of Altenschatten?