To be honest, I don't know a whole lot about Castle D. All I've really been able to gather is that this came out on B-Boy Records in '86. The beat kills for its time. Slow, dark and catchy. This, as well as TONS of other B-Boy classics can be bought as a whole (10 albums total!) as part of the B-Boy Records: The Complete Masterworks box set, or individually over here. Be sure to preview some of the tracks from the box set. There are quite a few gems to be found. (And if anyone can shed some more light on Castle D for me, please post in the comments below).