 Suzie Costello, as played by Indira Varma, had also been billed as a series regular prior to transmission, though in a twist the character was revealed as the murderer and killed off at the end of the episode, with Gwen replacing her as a member of the Torchwood team.The episode originally aired on freeview channel BBC Three and upon broadcast earned the channel its highest ever viewing figures.Critical reaction to the episode was mixed, with reviewers making both positive and negative comparisons to "Torchwood"s parent show "Doctor Who".