A fallen clock tower holds components from an ancient artifact. Upon discovery of the components, competing agents look to launch expeditions to uncover additional components scattered across distant places—and times. The now-lost Temple of Moloch and the construction site of the legendary Tomb of Horrors are two of those locations. However great the risks, finding the components demands the effort, for whoever does so can reassemble the fabled Infernal Machine of Lum the Mad!
Operating as secret agents for the Lords of Waterdeep, a promising lead takes you deep into the world of the Xanathar, but what will it take for you to return?