 The Rift first appears in the "Doctor Who" episode "The Unquiet Dead".This episode takes place in 1869, when the Gelth, gaseous humanoid organisms, pass through the Rift into a funeral parlour, where they are able to “possess” the corpses.It is established that the Rift releases radiation, prolonged exposure to which can grant psychic powers to people, including Gwyneth, a servant in the parlour.