Investigative journalist Jeff Sefton (Davis) has learned to live with his younger brother Nate's (guest star James Pizzinato "Alcatraz") relentless string of obsessions, especially his latest rant that a hit TV show called "Cult" intends to harm him. When his brother mysteriously disappears, Jeff enlists Skye Yarrow (Jessica Lucas, "Cloverfield," "Melrose Place"), a young research assistant working on "Cult," to help with his investigation into the dark underworld of the TV show and its rabid fans. Meanwhile, in the parallel worlds of the show-within-a-show, the cult's ruthless leader, Billy Grimm, is played by actor Roger Reeves (the double role of Billy/Roger is played by Robert Knepper ("Prison Break," "Shameless"), a man whose primary agenda is winning back his former follower and lover, Kelly Collins, played by actress Marti Gerritsen (the double role of Kelly/Marti is played by Alona Tal ("Supernatural," "The Killing"). Since escaping from the cult, Kelly has become an LAPD detective who finds herself drawn back into an investigation of the group's activities as she struggles to keep Billy at a safe distance.