Here is an attempt at the masquerade costume that Judge Turpin wore during Sweeney Todd the Demon Barber of Fleet Street. Or, it could be any gothic/victorianesque outfit for your dark sims. I do admit to being a bit rushed (by myself) with this outfit, and I apologize for the sloppy shoes (I can never figure those things out!).
I included a picture of Turpin wearing the costume in the movie, but he wears that coat over it everytime he is shown

I did, however, find some exhibit photos that showed me the costume under the coat. (Technically, the coat is part of the costume, but I found it a little boring in comparison with the rest of the costume, and did not include it)
The mesh is by the wonderful Sussi, and can be found here:
http://sumomo.modthesims2.com/showthread.php?t=215001Enjoy!