I have a directory as such:
D:\\Movies D:\\Movies\\MovieTitle1\\backdrops\\ D:\\Movies\\MovieTitle2\\backdrops\\ D:\\Movies\\MovieTitle3\\backdrops\\ D:\\Movies\
Above answer didn't quite work for me. I had to use a combination of @itd solution and @Groo comment. Kudos to them.
Final solution for me was (using the backdrop folder example):
FOR /d /r . %%d IN ("backdrops") DO @IF EXIST "%%d" rd /s /q "%%d"