G is for... Gelth

The Gelth were an alien race who had lost their physical forms as a result of the Time War between the Time Lords and the Daleks. They arrived on Earth in the 1860's through a rift in space and time centred on the Welsh city of Cardiff. Here they began to inhabit the bodies of corpses in the funeral parlour belonging to a Mr Sneed - reanimating the cadavers for a brief time. However, they found the planet's atmosphere hostile and reverted to a gaseous form. They felt most comfortable in the gas supply at Sneed's home. Sneed's servant girl, Gwyneth, had psychic abilities, and was able to communicate with them. The Doctor arranged a seance at which one of the Gelth appeared. She claimed that they were a benevolent species, few in number, and the Doctor felt responsible for their predicament as he had fought in the Time War. He agreed that they should be allowed to come to Earth and permanently take up new bodies from amongst the dead. Once the rift had been opened, however, it transpired that the Gelth were many, and they planned to take over the planet. The writer Charles Dickens was present during these events. He discovered that by flooding the environment with gas, the Gelth could be drawn out of their murderous human hosts. Gwyneth then sacrificed herself to seal the rift, destroying the Gelth and preventing more from crossing over to Earth.

Played by: Zoe Thorne. Appearances: The Unquiet Dead (2005).

• Thorne later provided the female voice for the Toclafane in The Sound of Drums / Last of the Time Lords.