DVD Talk's Jeffrey Robinson felt that Billie and Christy were the strongest parts of the season, and Sheldon Wiebe of the entertainment website Eclipsemagazine.com regarded the characters as re-establishing a "dark undercurrent" reminiscent of the show's first and second seasons.
According to Jeffrey Robinson of DVD Talk, Billie and Christy were the standout elements of the season, while Sheldon Wiebe from Eclipsemagazine.com believed they brought back a sense of darkness similar to the early and middle seasons.