It might be a bit odd to call this dress "lost" when it is present in every performance... but this is one of Christine's personal dresses which we in fact never see her wear, and as such it is an elusive dress. It is on display in her dressing room, between the door and the mirror, and has three purposes: 1. There is no wall there, so it fills in the blank space, 2. It serves as a "door stopper" as the door is flung open when Raoul e-enters, and 3. It makes it look even more like a dressing room. We might assume that Christine was to wear this the night after her triumphant gala, though it does look more like a walking dress than an evening dress.

The original "lost" dress had a shape reminding of Christine's blue "wishing" dress. The bodice and skirt matched, and the bodice had a contrasting collar and front area, but the sleeves were longer. The skirt had a fringed apron, but no side drapes. The colour seems to have been a greyish blue tone, in a patterned brocade or similar. It seems the dress is still in use in West End in the early 2000s, which is quite impressive. However, recent photos shows the version with a "Swiss bodice".

However, all other productions sports a different design. The dress is made of a stripy material, and has a "Swiss bodice". This was basically a sleeveless, corset like construction, often going under the bust, on top of the main bodice or as a part of it. Some productions have a plain "Swiss bodice" with only contrasting seams, some have a decorated front. The neck opening is usually V shaped and with a lace trim; some also have a medallion or cameo. The sleeves are elbow length and have lace engageants, as most of Christine's other dresses. The skirt is split in front, revealing a skirt underneath. This is often lace decorated or with other embellishment. Some dresses also have paniers; drapes going over the hips towards the back. The colours varies from golden to dark teal to b/w.