When Christine emerges after Buquet is hanged, she takes Raoul to the rooftop where "they will be safe there." Together, they confess their love for one another while Erik listens brokenhearted in the background. This outfit seems to take after the Elizabethen style corset and a very full,layered skirt. It's obvious that she is in a stage of undress, and we still wonder if she is cold with just that cloak on...
I don't think anything but her shoes were every auctioned off, and we have a very rare glimpse of the dreses without the cape.
Corset and chemise
The chemise is thought to be the same chemise she wears with the dressing gown. I myself am not sure of this because there is a pink bow in the front, but it still does look very, very similiar to the dressing gown chemise.
The corset is a very typical eliabethan corset. Tons of info on elizabethan costuming can be found here: Elizabethan Costume Page.
Note that the lace of the chemise extends over the corset itself. The stays are not fully boned like most stays are, instead, there is a bone every one inches. It is pointed in the front, traditionally, though.
Skirt
The skirt is of a very light, pink material, which is gathered very fully and only reaches her ankles. I have a suspiscion that it is a circle skirt. There are many layers to the skirt, though only one, obviously, is visible. Unfortunately, there aren't many shots of the skirt itself, making it difficult to make inferences.
The Cape
The cape is made from a very luxurious red velvet. The cape itself is very full, tied at the neckline with a gathered hood. The hood is also lined with a fine printed velvet, although I could be wrong on the type of fabric used.
I'm so sorry that I don't have much to tell you, but I'm trying!
Random
Costumers Guide has a few photos of this dress from the Bloomingdale's window display back in Christmas of 2004. You can see them here submitted by midnightstar88.
About.com has a short article and a few pictures here.
Shoes
There isn't much reference on this shoe, so I am still trying to find some kind of historical reference to these. If anyone has any information, don't hesitate!
Images:
Ebay Auction:
Other: