It's no ordinary heat that consumes me as I alight from the air-conditioned carriage of the overnight train from Puri. Sweat puddles are forming in my shoes. Kolkata's humidity is as intense and unmistakable as her people are proud and cerebral. Even my death-wish cabbie plays mind games. As he races invisible enemies, his eyes are on me in the rear-view mirror: it's more a battle of wits than a mere taxi ride.
To offset my neck's rail-induced crick, I head straight for Kaya Kalp, the substantial spa at ITC Sonar (00 91 33 2345 4545; itchotels.in), a plush resort-like hotel with vast lily ponds between sleek, sober blocks at the edge of the city. Two hours of muscle-fixing pummelling and Indian foot massage straightens me out.
Replacing my rally-ready taxi driver is one of Sonar's liveried, white-gloved chauffeurs; he delivers me to The Oberoi Grand (00 91 33 2249 2323; oberoihotels.com), my hotel on the heaving Jawaharlal Nehru Road, the city's furious main artery. It has 125-year-old bones, gracious staff and palm trees around the pool – and from the street you hardly know it's there. My suite is a study in restrained opulence; a timeless cocoon with contemporary enhancements and a balcony overlooking the poolside loungers, where I spend hours being fawned over by staff bearing water, sunscreen and cocktails.
Although the temperatures are appetite-suppressing, Kolkata's food scene is legendary, so I head to Old Ballygunge to seek out chef Joy Banerjee's trendsetting restaurant, Bohemian (00 91 33 6460 1002; chefjoybanerjee.com). Tucked away down a nondescript bylane, its menu is exciting Bengali-with-a-twist: I suck down delectable prawns soaked in vodka.
For after-dinner coolers, I swing up to Shisha Reincarnated (00 91 33 2281 1313; shishareincarnated.com), a lounge bar serving frozen shooters to a good-looking crowd. Elegant inside, its deck provides a fantastic view of the city.
The Park (00 91 33 2249 9000; theparkhotels.com) on Park Street is another swish hotel, but it feels like stepping into a club or perhaps a chichi gallery. No time for ogling, though, since stiff licensing laws necessitate cramming in as much of a good time as possible before midnight closures – 2am at a push. I follow my ears from the lobby and into Tantra, one of three rammed in-house clubs, where killer electronica has hypnotised a room full of revellers.
The next morning, a polite wake-up call alerts me to my waiting taxi, summoned to take me to the local flower market, where I nurse my groggy head with sweet chai while watching stallholders deftly string marigold garlands for the gods.
The midday sun is cooking and Kolkata has slowed to a crawl. I slink back to the hotel pool and melt. After a cold shower, I'm ready for more, starting with dinner at Saffron, The Park's cutting-edge fusion restaurant, which serves Anglo-Indian curry. I'm going to need a boost if I'm to keep up with the party crowd later. Daytime may be ruled by lethargy, but at night, Kolkata's pulse rages strong.
A Hedonist's Guide to ... (Hg2) is a luxury city guide series for the more decadent traveller. For further information see hg2.com