On one of her nightly outings, Annie encounters Sasha (Alexandra Roach), a woman who is clearly dead but also corporeal. Sasha follows Annie home, where George, Nina, and Mitchell are stunned to realize Sasha is a zombie (a "Type 4" in the nomenclature of Kemp's organization from Series 2). Sasha refuses to believe she's dead, and Annie tries to help her confront the truth. Meanwhile, Mitchell discovers Sasha isn't the only zombie, and that hospital personnel have performed horrific experiments on the others. (This ties in with the final moments of the previous episode.) Mitchell also discovers he has a groupie, Graham (Tony Maudsley)—an overweight, nerdy, middle-aged vampire. Graham's obsession with Mitchell quickly grows out of hand, and he not only insinuates himself into Mitchell's life but says he will tell George, Nina, and Annie about Mitchell's complicity in the Box Tunnel murders if Mitchell tries to stop him. As George and Nina discover that Nina might be pregnant (which comes with its own revelation about Nina's past), Mitchell must confront Graham before Graham reveals Mitchell's secret or does something even worse.