Next Doctor Who: Fans believe series 10 finale holds key to who will replace Peter Capaldi as the Doctor

** Spoilers for 'The Doctor Falls’ ahead **

Doctor Who’s most recent series finished with an emotional farewell to various characters, possibly including Pearl Mackie’s Bill.

Of course, the episode also marked Peter Capaldi and Steven Moffat’s last main-series outing, the duo only having the Christmas special left.

Attention has, as you would expect, turned to one question above all others: ‘Who will replace Capaldi as the Doctor?’ Some fans believe Capaldi may have hidden a clue in the finale.

Towards the end of the episode, Bill steps forward to tackle whatever horror comes form within a black hole the group are speeding towards.

The Master then asks “Will the future be all girl?” to which The Doctor replies: “We can only hope”.

Viewers immediately jumped on the quotes, believing it to be a not-so-subtle reference to The Doctor regenerating as a woman next time around.

Twitter was split on the callout, some believing the iconic character should remain male, while others praised the possible change — something that has been discussed multiple times over the years.

One possible candidate includes Fleabag’s Phoebe Waller-Bridge, who is currently working on the muddled Han Solo movie. However, she faces competition from Love Actually and My Family’s Kris Marshall, who betting was suspended on earlier this year.

Whoever takes the role, they will join Capaldi, along with The First Doctor, in this year’s Christmas special, which will be broadcast Christmas Day on BBC One.