From the introduction:
A vile sickness creeps through the rookeries of Ubersreik. When an investigating doktor discovers the infection spreading from one tenement in the Spittlefeld slums, the building is quarantined immediately. Armed members of the Watch are posted on all exits, and crossbows are aimed at every window. No one goes in. No one comes out. For the unfortunate souls trapped within, there is little hope of escape unless they can find the cause of the infection. But that wants out, too. And if it can’t break free? Well, it won’t be the first time there is a Slaughter in Spittlefeld...
Ubersreik Adventures: Slaughter in Spittlefeld is an adventure that explores the horrors of disease, and how it erodes not only the flesh, but also the minds of friends and neighbours alike. It takes place in Ubersreik, but could be moved to any suitably large city or town of the Empire. This adventure is suitable for four to six Characters in their 1st or 2nd Career, and should take about 4 hours to complete.