Now that you've got some experience as an Evil Doctor, it's time to move onward and upward. Where's the place to be in the Evil Doctoring World of the late 1800s? London. What's your plan? Find a cheap warehouse somewhere to build your Doomsday Machine. Scotland Yard is on your trail, however, so in addition to your Doomsday Machine, you'll have to build an Escape Plan.

In the worker-placement style game What's He Building in There?, players use their Doctors and three henchmen to acquire resources at the available shops, acquire gold, visit the black markets, provide the "Genius at Work" labor (GAW), provide "Manual Labor" (ML), improve the Doctor's social standing, and invent things. You must complete both a Doomsday Machine and an Escape Plan, with higher level Doomsday Machines and Escape Plans garnering more victory points, and you need to do it quickly. Scotland Yard is getting suspicious, after all, so you have to do what you need to do in 15 turns. Players can earn additional victory points for fitting in with society, eccentricity, security and inventions.

Play time is approximately 25-30 minutes per player.