Consequently, a glamorous, avant-garde and more "material" Shanghai emerged and dominated the HK-Shanghai dialogue for the first half of the 20th century but back then, was there any talk of superiority as there is now?

"No, because Shanghai was unquestionably better, and more desirable," says Chan, pointing to a mini comic film from that era, in which people of all ages and professions were seen thronging the train station shouting in unison "Shanghai! Shanghai!".

"Shanghai's famous ballrooms were transplanted to Hong Kong, as well as the ladies who were 'queens of the dance floor'," says Chan. "But more importantly, the mass flight of the city's industrialists, capital, facilities and technical know-how from Shanghai migrated to Hong Kong, stimulating the development of the island's Chinese-funded industries."

The cultural scene also flourished, with such institutions as The Commercial Press in Shanghai relocated to Hong Kong in 1937.

In the following five decades, the two cities drifted increasingly away from each other and Hong Kong was to emerge from the shadow of her "big sister".

"Hong Kong saw a full ascendance of its confidence in the 70s, around the same time as the so-called 'Hong Kong identity' was forged," says Ting. "Second-generation immigrants, born in the 1940s and 50s, had grown up knowing nothing about the previous history of Hong Kong and Shanghai. For them, Hong Kong was the best."

This mentality may partly explain why some in Hong Kong may view Shanghai's transformation into an international financial center with a mixed feeling of disbelief and angst.

Naturally, the two cities viewed their shared histories differently. For Hong Kong, it is the beginning of a success story that gets a mention at every museum exhibition on the topic. For Shanghai, it is the most intriguing chapter in its thick volumes of history.

"In a sense, Hong Kong has moved on, whereas Shanghai has stuck to its past, reminiscing endlessly about a bygone glory," says Ting, who nonetheless believes this nostalgia could be a driving force for Shanghai's resurgence.

And it still has the advantage it has always had - an enviable geographical location, close connection with the mainland and a broad vision of the world.

"Hong Kong was so immersed in British culture that Britain is still the top destination for youths studying overseas," says Ting. "Shanghai students, on the other hand, choose freely among several countries. They will undoubtedly bring back a plethora of thoughts and ideas beneficial to Shanghai's future development."

Could Hong Kong lose its competitiveness and charisma, once Shanghai recaptures its dream? "Mainlanders may still come to Hong Kong to buy Louis Vuitton bags but rich HK wives are already flying to Shanghai for their weekend shopping," says Ting.

"Like it or not, the lights are on - and it's not just in one place."