H is for... House

House was the name of a disembodied entity of incredible power, which inhabited a small planetoid in a bubble universe. It was called House as the planetoid was home to a number of beings who had become trapped there, and who were looked after by the entity. It kept them alive by using the body parts of others who had been lured there - primarily those of Time Lords, as House fed on the energy of TARDISes. House manifested itself as a glowing green gas. On capturing a TARDIS, it would deposit the ship's matrix inside one of its people, to expire when they burned up and died.
The Doctor was lured to the planetoid when he encountered a Time Lord message cube, and thought that he had found another survivor of the Time War. This proved to be a trap, as House had a number of such cubes. The Doctor's TARDIS had its matrix downloaded into a woman named Idris. House had learned from the Doctor that there were no more TARDISes left, so it decided to transfer itself into the Doctor's ship and leave the bubble universe. Amy and Rory were trapped on board as it left, leaving the Doctor to work with Idris in building a makeshift TARDIS from the wrecks left behind so that they could follow. Inside the TARDIS, House played sadistic games with the Doctor's companions, distorting their reality before killing them. The entity also inhabited an Ood named Nephew, which threatened them - its eyes glowing green.
After the Doctor and Idris caught up with the ship, destroying Nephew as they materialised on board, House decided to kill everyone by ejecting them from the ship. Safety protocols deposited them instead inside the console room. Now that Idris was aboard, the TARDIS matrix was able to leave her and re-enter the ship. It overwhelmed and consumed House.

Voiced by: Michael Sheen. Appearances: The Doctor's Wife (2011).

• One of the highlights of lockdown has been the BBC TV series Staged, wherein Sheen and David Tennant have appeared together as themselves in a number of video calls regarding working together on a play. If you haven't seen it, please check it out - it's very funny.
• The two starred alongside each other in Neil Gaiman's adaptation of his and Terry Pratchett's Good Omens, as demon Crowley and angel Aziraphale.
• Both also appeared together in Stephen Fry's film Bright Young Things.
• One of Britain's best known actors, Sheen has appeared in a number of genre movies, including the Twilight and Underworld werewolf / vampire franchises.
• He has a habit of essaying real people in his performances - individuals ranging from TV presenter David Frost (Frost / Nixon), comic actor Kenneth Williams (Fantabulosa!), football manager Brian Clough (The Damned United), UK Prime Minister Tony Blair (C4's The Deal and then again in movie The Queen) and TV presenter Chris Tarrant (Quiz). He has also played the Emperor Nero on TV, and Caligula on stage.