Is that a plunging V-neck top that Joanne Peh is wearing?

Celebrities sparkled as brightly as the 21m-tall Christmas tree unveiled by Louis Vuitton outside Ion Orchard on Nov 15 evening.

Among the glitterati was actress Joanne Peh wearing what appeared to be a revealing low-cut top.

After she posted images of herself at the event on Instagram, netizens commented with adjectives like "stunning" and "sexy".

But other comments were less flattering.

One netizen remarked: "Oh my, that white dress isn't really fitting and unsightly."

Another said: "Very self-confident to wear this outfit. Lots of fashion tape I bet. Victim of fashion or leader of fashion."

To which Peh herself replied jokingly: "Who needs tape when I have posture?"

The not-so-secret secret is that what she wore was not what it seemed.

The top half of her LV jumpsuit actually has a "sensual sheer insert on the chest to create a daring plunging V-neck effect", to quote the fashion brand's website.

If you fancy one for yourself, it retails at $8,350.

Other celebs who graced the festive tree-lighting ceremony included Zoe Tay, Fann Wong and Christopher Lee.

If you fancy one for yourself, it retails at $8,350. Other celebs who graced the festive tree-lighting ceremony included Zoe Tay, Fann Wong and Christopher Lee.