When the Doctor diverts an asteroid from its collision course with Earth, the TARDIS is invaded by an ancient menace: a Solonite. Racing to save her friend’s life, Rose lands the TARDIS in Northumberland, Earth in 1986, and they find shelter in an isolated farmhouse. Teaming up with Peggy, a grieving artist, the travellers realise the terrible truth: the Solonite has accompanied them to Earth, and is now at large. As the terrifying entity seeks to possess them, its fearful purpose becomes clear – and it involves the TARDIS…