This 1724 town house was dragged down by a declining neighborhood until the 1970s, when eccentric Californian Dennis Severs purchased it for a pittance, dressed it with antiques, and delighted the intelligentsia with this amusingly pretentious imagination odyssey—he called it “Still Life Drama.” Other museums are unrealistically neat and cordoned off, but his house looks lived-in, so the past feels as real as it truly was. As Severs, who died in 1999, put it, “In this house it is not what you see, but what you have only just missed and are being asked to imagine.” You could go during the day, but it’s best on Monday, Wednesday, and Friday after dark for “Silent Night.” As you approach, the shutters are drawn and a gas lamp burns. You’re admitted by a manservant who speaks little. He motions you to explore the premises, silently and at your own pace. Suddenly, you’re in the parlor of a prosperous merchant in the 1700s; the owners seem to be home but in the next room. Candles burn, a fire pops in the hearth, the smell of food wafts in the air, and a black cat dozes in the corner. Out on the street, you hear footsteps and hooves. Room by dusky room, you silently explore corners overflowing with the implements of everyday life. It’s as if the residents were just there, leaving toys on the stairs, beds rumpled, mulled wine freshly spilled, tea growing cold. By the time you explore the attic, you’ll have accompanied the house and its occupants through its decay into a collapsing slum. “Silent Night” is one of London’s most invigorating diversions.