Here we go again. Another downtown hideaway fourteen minutes away from certain overexposure. We wandered into this one just as the paint was drying. The owner, Johnny B., was real nice about giving us the scoop, but he asked that we keep certain things off the record. Ah, well. Loose lips sink ships. (But let’s hope the hush can outlast the day.) We can give you the actual name (The Back Room) and location (Norfolk), but take note that the entrance isn’t on the street and the front’s a fake made to look like a ’20s-era toy store. The bar is a beauty — art nouveau furnishings, chandeliers, candlestick phone, even a nickelodeon. It’s an homage to the Roaring Twenties and the space’s alleged gangster history. But the real hidden gem here is a secret speakeasy within the bar — a stunning Prohibition setup accessed only from behind a trick bookcase. Sorry, invited guests only. So befriend one of the celeb partners if you want the password. And in the meantime, hang with barflies and order a cocktail in a teacup. As for the rest of the story? We can’t say. Or we’ll end up sleeping with the fishes. The Back Room, 102 Norfolk Street, between Delancey and Rivington Streets (212-228-5098).