2.30am: The air outside my Bangkok hotel is warm, moist and perfumed with a whiff of frangipani. Although the roads of Thailand's capital city never actually sleep they are least slumbering as we head for the airport.
8am: Sunlight is glancing off the saturated, pearly landscape of early morning over Bangladesh. As we descend towards Kolkata however, a swathe of palm trees transforms the landscape green, with the occasional mould-splashed concrete building emerging from the fronds. When we land the windows of the Druk Air (Bhutan's national carrier) plane immediately fog up in the humidity.
8am: We're moving back in time but now flying north - 40 minutes from the Bay of Bengal, out of India, briefly back into Bangladesh airspace, back into India and then before us the Himalayas and the mountain kingdom of Bhutan. Off to the west, rising above a tumult of cloud is Everest and closer to us, Kachenjunga - the world's highest and third highest mountains respectively - viewed over the rim of an orange juice.
9am: We begin to descend into Bhutan. This has to be one of the world's best, if short, white-knuckle flights. Hillsides clad in blue pine loom up on each wingtip as we wend our way along a river valley to the airport.
Prayer flags flutter above us on the wooded ridges, rice paddies now beginning to turn to burnished gold, signalling the onset of harvest-time and autumn, fill the windows as the plane banks steeply to round the bends of the river; we fly so close to some of the farm houses we can almost count the bright red chillies drying on the shingled roofs.