comawhites:

 We’ve been searching for someone with a special trait. A direct descendant of Alexander Corvinus, Hungarian, a warlord, who came to power in the early seasons of the fifth century. Just in time to watch a plague ravage his village. He alone survived. Somehow, his body was able to change the disease mold it to his benefit. He became the first true immortal. And years later, he fathered at least two children who inherited this same trait. The sons of the Corvinus clan. One bitten by bat, one by wolf, one to walk the lonely road of mortality as a human. It’s a ridiculous legend. Nothing! That may be, but our species do have a common ancestor. A mutation of the original virus is directly linked to his bloodline. There is a descendant of Corvinus lying there, not three feet from you. Yes. But he’s already a vampire. We needed a pure source, untainted. An exact duplicate of the original virus, which we learned was hidden away in the genetic code of his human descendants and passed along in its latent form down through the ages all the way to Michael Corvin. For years, we tried to combine the bloodlines. And for years we failed. It was useless. Even at the cellular level, our species seemed destined to destroy each other. That is, until we found Michael. The Corvinus strain allows for a perfect union. A triple-celled platelet which holds unspeakable power.

Underworld (2003), dir. Len Wiseman