Her first outfit, a royal purple Bottega Veneta gown had a neckline that plunged to her waist and a dramatic long train. Only a sheer black lining preserved her modesty from the front.
To Peh's credit, she carried off the daring dress with confidence, cheekily swishing her long train as she walked down the red carpet to cat calls and wolf whistles from fans and members of the public.
"I was just worried about stepping on the gown... we (with fellow actress Rui En) were thinking, our dresses are so long, how are we going to walk in properly... but I think we did it quite well," said Peh in Mandarin.
She later changed into a slightly more conservative shimmering silver gown which was held up by three black straps but still exposed much of her back and side.
In her surprise win, Peh beat the likes of "Ah Jies" (elder sisters) Zoe Tay and Fann Wong to snag the Best Actress award for her role as a haughty model in the Channel 8 drama, "A Tale of Two Cities".
The actress, who just turned 30 last week and is currently dating American actor/local deejay Bobby Tonelli, was visibly shocked when the results were announced.
During her emotional thank-you speech, she said she knew everyone had their favourites they were rooting for, but she hoped that viewers would "give me a chance and room for making mistakes so I can perform better."
Backstage, she told the waiting media that her "mind was in a blank" and that she was "still feeling very emotional" and didn't expect her win, reported The New Paper.
This is the second Best Actress win for Peh, who beat out hot favourite Jeanette Aw to win for her role as Huang Yuzhu in Channel 8 drama The Little Nyonya in 2009.
However, Joanne wasn't the only Mediacorp actress flashing the flesh on the red carpet on Sunday night.
Actress Constance Song turned up in an even more jaw-droppingly titillating gown that left little to the imagination.
From afar, Song's dress appeared to be held up by mere strings in a gravity-defying miracle but up close, it was revealed that there was a clear mesh holding her dress together all the way to her navel.
Song told The New Paper that she was not too concerned about a wardrobe malfunction.
"I wasn't worried that I would reveal too much because when I move, the dress doesn't move at all." said Song, whose gown was by designer Jeanette Ivarson's Jiki label.
She even did a quick spin after host Dasmond Koh told her to show her dress off.
When asked by Koh what she thought of her dress, the actress paused before quipping in Mandarin, "Need I say more?"