For thousands of years, the world has been controlled by the "50 Families" -- a secret network of vampire covens engaged in a timeless struggle for power. But when the sun rises, the vampires are forced to employ the services of a human who acts as their daytime fixer and protector...Trained for centuries to be the mortal soldiers of their vampire employers, the Day Men go forth at sunrise, alone into the world, to do the bidding of their sleeping benefactors.