Doctor Who: 10 Dropped Plot Threads We'll Never Get The Answer To
7. What Happened To Nardole?
Nardole was an unexpected addition to the TARDIS for season 10. Going by Matt Lucas' broad turn in 2015 Christmas special 'The Husbands of River Song', fans weren't expecting much, but the character actually turned out to be an entertaining companion for the Doctor and Bill.
Which is why it's still annoying that he never got a proper ending, as finale 'The Doctor Falls' last catches up with Nardole as he escorts a load of orphans away from the Cybermen. It's a neat end to his character arc as it shows that he's grown braver, but it also leaves his fate open-ended. There's a real chance he could have died in the battle with the metalheads.
The Christmas special 'Twice Upon a Time' confuses things by featuring a glass replica of Nardole, courtesy of the Testimony. It's established that these are effectively A.I.s of the dead. So does that mean he didn't make it out alive?