It is 11:15 on a sunny Sunday morning across the road from Shinjuku Station in central Tokyo. The Southern Terrace there is already thronged with shoppers like all the city's other retail districts. And then, as you walk past fashion stores and coffee shops, a long line of men and women of all ages materializes before you.

What you are beholding is one of the latest and most famous queues in Tokyo — the one snaking toward a Krispy Kreme doughnut shop that opened late last year. On this particular Sunday, some 150 people were shuffling along in six lines spawned by the shop, filling the space outside — with another crowd of around the same number waiting, like military reinforcements, ready to step into the ranks as those before them, all sticky and smiling, moved on.

And wait they must. As the mercury rises toward noon, the lines just get longer and longer. Despite the shop's notice board announcing that those at the end of the line will have to wait at least 1 hour and 50 minutes for their sweet, circular fixes, there's no letup in the arrival of new recruits.