Ever since the first Gardella was called to fight vampires in First-Century Rome, members of the Gardella family have been chosen to take up the duty of ridding the world of the evil undead.

Those selected for this responsibility are warned through a series of five horrible dreams within a short time–dreams that demonstrate and portend their future of hunting vampires and battling evil. Many who are called don't know the meaning of the dreams until after the fifth one, when they are educated about the world of vampires and Venators by a mentor that is sent to them.

Once the dreams have occurred, and if the dreamer agrees to accept the Legacy, the chosen person must pass a test: to hunt and kill a vampire. One who is called to this duty bears the innate sense and skill to carry out this duty, although he or she may decide not to accept the calling.

If the chosen Gardella is successful in slaying a vampire, then he (or she) is given the vis bulla and becomes a full-fledged Venator, or vampire hunter.

The vis bulla is a holy strength amulet, a tiny silver cross forged from a small vein beneath the mountain of Golgatha and steeped in holy water. It provides protection, strength, speed, and fast-healing capability for the Venator.

There are no more than two hundred Venators world wide at any given time; they fall in far-flung branches of the Gardella family throughout all corners of the earth–often unaware of the family legacy until the  five dreams, and the subsequent visit by the mentor.

These randomly-appearing members of the Gardella family tree are known as born Venators, for they were born to their duty and chosen for the Legacy.