10 Doctor Who Revival Era Monsters And Villains That Deserve To Return
8. Gus
Mummy on the Orient Express was one of the best episodes in a lackluster season of new Who. Strangely, it had been teased years ago when the Doctor got a phone call in the Tardis asking him to come stop a Mummy, and after a regeneration and a few years he finally does.
The Monster of the episode is the eponymous mummy, who only appears to its victim 66 seconds before they die. But the twist is that everyone on board is there on purpose, so they can study to phenomena and potentially weaponize it.
It is the ship's A.I., Gus, that relates this to The Doctor, and motivates him in killing some of the ships inhabitants. The Doctor figures out how to stop the monster, and of course the train blows up.
He can’t track down the people that brought him there, so, curiously, he leaves it there. Usually when someone has knowledge of who the Doctor is, and utilizes him to their own ends, he doesn’t take it so well.
This is just a nagging loose end really but it could be taken in any direction, an insidious organisation, with knowledge of who the Doctor is and ability to call the Tardis. As a pitch that’s not bad on its own. Plus fans always love a loose end mop up, so why not.