THE DOCTOR: The Twelfth Doctor is older, gruffer and much more pragmatic like the First Doctor, a science-minded individual with a stance like the Third, and with a little bit of insanity like the Fourth. And yet, despite his seemingly uncaring exterior, he protects those he cares about with the same ferocity as every Doctor does. But the Doctor is not without his limitations. From 'Listen', it's clear that his fear of the things that go bump in the night war with his natural curiosity and it's a combination of the two that spur him on to fight every battle. THE ENEMY: Fans of the Tenth Doctor's era will remember and be frightened all over again by the Vashta Nerada, the swarm of microscopic carnivorous beings that strip the meat from their victims' bodies in a matter of seconds. These sentient swarms live in darkness and cast shadows when they entered the light, and hatched from eggs in trees and books. THE BATTLE: How would the Twelfth Doctor hold up against them speeding towards him and gradually blotting out the light, or the skeletal bodies from 'The Library' repeating "Hey, who turned off the lights"? Surely the Doctor will have flashbacks to the times he hid from the darkness, and the things that lurked within, and feel that creeping, agonising fear. A scientist he may be, a teacher at heart telling others to "get it right!", but the Vashta Nerada speaks to something deeper and more primal within a man. Trapped with nowhere to go, with his life and his companion(s) a moment from ending, the Twelfth Doctor will have to remember that same courage and ferocity to defeat a foe that thrives in the mysterious, inky blackness. ALTERNATIVE ENEMY: Alex Salmond, trying to get him to support Scottish independence. What do you think of this list? Are there any other Doctor/monster mash-ups you would like to see? Share your thoughts in the comments below.