After dinner, there's nothing I like better than a digestif—or two—to lull me into sleepiness. Tonight, I've arrived post-repast at Lebensstern, located in silent film star Henny Porten's former Berlin mansion. The host has led my group to a cluster of heavy club chairs in a red-walled parlor that feels like a 1920s salon. It is lined in glass cabinets displaying the bar's collection of 1,800 spirits, many of them rare. Around us, tuxedoed revelers sip bespoke cocktails from silver flutes or ice-encrusted goblets: an amaro-laced Lucky Luciano; a citrusy Pop Rocks-rimmed Lime Pie; a Nectar of the Ancient, made with cardamom extract and resinous Greek liqueur. Most drinks contain a splash of surprise like honey vinegar, orange mustard, or an herb grown on the terrace. We sit so long, we lose hours here; it feels like a place outside of time. Eventually, the host suggests a final nightcap (a Guadeloupe rum aged for 42 years in an armagnac cask tempts me) as a civilized reminder that the party is nearing a close.