Imagine you are looking for a drink in New York in the 1920s. You have dressed for the occasion, perhaps put on a feathered headband, and followed a friend down a dimly lit street. There is no signboard, no welcoming neon, and certainly no bartender waiting to take your order. Instead, you find an unassuming door, knock a certain number of times, whisper a password, and hope that whoever answers knows you.






