This isn’t the only Hill House out there,” says architect Robin Donaldson. He’s right: Historic homes with that title dot the map from Scotland to Arizona; novelist Shirley Jackson famously borrowed the name for her 1959 Gothic classic, The Haunting of Hill House. Like its spooky fictional counterpart, the 10,720-square-foot concrete structure that Southern California-based Donaldson + Partners created for art collectors Bruce Heavin and Lynda Weinman in Montecito, California, is big, a little odd, and full of curious secrets that slowly reveal themselves over time. Fortunately, this Hill House is a lot cheerier than Jackson’s.