The Doctor takes Rose back through time to 1869.  But in Victorian Cardiff, the dead have been reanimated.  The Doctor and Rose meet Charles Dickens and they are able to talk to the possesors of these people, the Gelth, with Gwyneth's help.  When the Doctor learns that the Gelth are victims of the Time War, he agrees to help them come through the time rift to inhabit the dead bodies of humans.  Once they start to come over though, they have other plans.  The TARDIS crew are able to get away after Gwyneth sacrifices herself to save the planet.