We told you last month that the True Blood Powers That Be were looking to cast two more vampires to boost the undead numbers in Bon Temps. They have now found one, formerly of Sherwood Forest. It’s Lucy Griffiths, lately Marian in the BBC series Robin Hood.

TV Guide reports:

Griffiths will play Nora, another vampire sired by Godric, making her the vampire sister of Eric (Alexander Skarsgard). Nora is described as intelligent and intimidating, along with being a good liar, which serves her well as a double agent within the Vampire Authority. Though she loves Eric deeply, she’s dedicated her life to a higher purpose.

A higher purpose. On True Blood? And when they say “loves Eric deeply,” do they mean sisterly love? Does that matter on True Blood? All these questions and more may or may not be answered when the new season premieres …

True Blood is reportedly returning for Season 5 in 2012 on HBO.