Blade: The Series plot
Krista Starr returns from military service from Iraq to find that her younger brother Zack has died under mysterious circumstances. Her investigation reveals that Zack was a "familiar", a servant of vampires. Her search for her brother's killer brings her face to face with Blade and the killer himself, the mighty vampire Marcus Van Sciver. Marcus is impressed by Krista and decides to turn her into a vampire too. Krista is approached by Blade who injects her with the same serum he uses to control his vampire instincts. He then offers her the chance to help him avenge her brother by defeating Marcus and his House of Chthon. The two form a partnership.