Red Dice (The Last Vampire, #3)

Alisa and her partner, Joel, are vampires. But Joel is also an FBI agent, and someone inside the government has discovered their secret. The government wants their blood, to study it, to duplicate it. They send a massive manhunt after Alisa and Joel. But using skills and abilities developed over 5,000 years, Alisa manages to elude the hunt. Unfortunately Joel is caught, and taken to a top-secret base in the Nevada desert. Now it is Alisa's task to free him before the scientists break the DNA code of their blood, and transform the whole world into vampires.