1610. All of Europe teeters on the brink of war. Religious and political factions manoeuvre for advantage. In the scramble for power, lost knowledge is brought to light, and discoveries from the New World change our conceptions of reality. But, there are some things man was not meant to know. The Heydelburg Horror, the first part of an epic campaign for Clockwork & Cthulhu, takes agents of the Karolinium in Prague across Europe to the dark secret at the heart of the Holy Roman Empire.

Requires the Clockwork & Chivalry Core Rulebook, 2nd Edition.