Assumin the background is perfect black and what you want is properly lit then you can do this. You could use the secondary color corrector or use chroma keying to remove the black and replace it with whatever is on the track below.
Bob.
I think he's saying to make the dancer look like an animated black figure. I don't know how to do this, just trying to get the answer to this in case I need it someday.
(that's the 2nd time this has happened to me today, where the answer appeared above me, as I'm typing in an answer.
There are two tutorials on this technique, one from me, and a better one from Johnny Roy, both found on the VASST site. I built this small veg file for you and zipped it with media. about 3 meg...Get it quick, because I'm running out of room on that server, and so will delete it tomorrow.
I hope it helps you figure it out.