Zillow Gone Wild (now a TV show hosted by Jack McBrayer) has a regular feature called You Never Know What's Going on Inside a Home. The point of this series is that fairly ordinary homes can have extraordinary features inside.
For example, this 5-bedroom, 9-bathroom mansion in Brentwood, Tennessee has an ice cream parlor in the basement with room for three tubs of ice cream to be displayed.
The other side of parlor has booth seating that is very convincing to guests that want to believe that they really are inside a vintage parlor.
The basement layout is amazing. You can see the entrance to the ice cream parlor on the right. Outside is a theater with seating for 60 people in front of a facade of an American main street.
You can window shop along non-existent shops before catching a show.
But go upstairs and outside and it looks like a completely normal home!