From the publisher's website:
ZEITGEIST is an adventure path for D&D 4th Edition and PATHFINDER RPG, taking a party of heroes from Level 1 to Level 30 (D&D 4E) or 1st-20th Level (PATHFINDER), brought to you by the same people who created the critically-acclaimed War of the Burning Sky campaign saga and featuring the same level of intriguing plot, memorable NPCs , and a strong, immersive storyline.
In the ZEITGEIST campaign saga, your characters serve in the Homeland Constabulary of the nation of Risur, protecting the country and its citizens from foreign threats lurking within Risur’s borders. During missions of espionage and assassination, your duty will be to root out hostile spies and pursue international conspiracies. As you learn more of your homeland’s own secrets, however, your loyalties may be tested, may even be turned, and you may find that it is you whose hand controls the gears of the turning age.
The ZEITGEIST campaign saga consists of twelve intricately crafted adventures, and is carefully designed to allow starting and stopping points (covering each of D&D 4E's tiers of play in the 4E version) while providing a cohesive, well-plotted story arc. The ZEITGEIST campaign saga is available to EN World subscribers.