But my question would be: How much of the script of "Rise of the Lycans" was written, when you wrote "blood enemy"? How much of the actual plot could you use? Or did the "Rise of the Lycans"-authors read your book and said: "Hey, that's awesome, we take that?"
Oh, "Rise of the Lycans" wasn't even a gleam in anyone's eye when I wrote "Blood Enemy," five years earlier. I wrote "Blood Enemy" (my only original UW novel for the uninitiated) right after the first movie, when they were still developing the plot for the second film, "Underworld: Evolution." The third movie, "Rise of the Lycans" was still years away, so nobody was scripting it yet.
In fact, as I recall, there was an issue with "Blood Enemy" in that the character of Marcus, a legendary vampire Elder, hadn't even been cast yet, so I had no idea what he looked like when I used him in "Blood Enemy."
Ironically, the whole reason we went the prequel route with "Blood Enemy" was to
avoid conflicting with any future sequels to the first movie, figuring that the movies would be going forward, not backwards. Little did we know that, half a decade later, the movies would do the prequel thing, too.
Which means I got to write a novelization that rendered my previous novel apocryphal.
(To be clear, I don't think the filmmarkers actually borrowed anything from "Blood Enemy." We were both just fleshing out the backstory as related in the original movie.)