The party were all summoned to a tavern by individually addressed letters from a shadowy organization known as the Neighborhood Watch. They might be a vigilante group, they might be organized crime themselves, but nobody really knows. Anyways, the party sits down at the corner table at the pub and an agent of the Watch shows up and hires the party to investigate kidnappings within the city which lead to people waking up on the streets with arms, legs, or even sometimes eyes being swapped with mechanical replacements. The party staked out an alley near the Steamworks, where the party concluded the trouble started, and followed a shadowy figure with augmented legs into a grate, which led to the relatively unexplored mechanical underworks of the city. The party killed a group of husks on a catwalk over a river of lava and fought three clockwork riflemen and a horde of mechanical spiders in a huge gear room.