The upcoming Doctor Who Christmas Special, 'Twice Upon a Time', is going to be an important and emotional one for fans of the show. It features the very last appearance of the Twelfth Doctor played by Pete Capaldi, before he regenerates into the Thirteenth Doctor played by Jodie Whittaker. However, a behind-the-scenes look at the production, suggests that Capaldi's final scene may not be the only heart-breaking moment in the episode. Another sequence reportedly left the crew and cast reportedly 'shell-shocked' and 'in pieces' after filming had stopped.

The 2017 Doctor Who Christmas Special has been building up hype ever since it was announced by the UK's BBC. Not only is it important for the departure of Capaldi, and the emergence of the first female Doctor, it also sees long-time showrunner Steven Moffat leave the show and Chris Chibnall take over. Pearl Mackie is getting another opportunity to give a final farewell to her character of 'Bill', and has appeared prominently in recent promo images. The whole episode itself will be steeped in nostalgia, as David Bradley reprises his portrayal of the First Doctor, a part he nailed when playing William Hartnell in An Adventure in Space and Time. All in all, it looks to be crucial viewing for fans of the show and a big step forward towards its next phase.

However according to the Radio Times, the most emotional moment may not originate from the climatic regeneration. UK radio personality Jo Whiley was on the set during the last days of shooting while pulling together a new audio documentary, and discovered the whole crew were still a little traumatized from a surprisingly emotional scene they had just shot. She said:

Doctor Who - The Doctor (Peter Capaldi) and Bill (Pearl Mackie)

“The day before there was a scene that they had to film, and everyone said EVERYONE was in tears. Because of the poignancy of the scene that they were filming, which had less to do with the Doctor himself and more to do with the storyline. And everyone was in pieces... And when you watch the Christmas Day episode, you’ll understand. It’s really very very clever, and very laced with emotion. It was less to do with the departure of the Doctor and more to do with the storyline... There were tears being shed everywhere.”

As Whiley points out that it was not the regeneration scene, several other possible moments stand out as likely candidates. The Twelfth Doctor's final farewell to his loyal companion Bill is an obvious choice. Mark Gatiss plays a World War I Army Captain who is destined to die on the battlefields, before he gets whisked away by the Doctor. Does he sacrifice himself at some point to save the future? Previous reports from the BBC also suggest a very sad scene between the First and Twelfth Doctor that will hit fans where it hurts. Does their reflection on their respective past/future cause some tears?

At any rate, 'Twice Upon a Time' is building up expectations nicely and looks to be an epic finale for all of those that are leaving the show, and a good chance for viewers to wallow in the history of the franchise during the festive season. Early footage already shows some effective verbal sparring between Capaldi and Bradley's Doctors. Hopefully, the episode lives up to the hype and Capaldi is given the sendoff that he deserves.

MORE: How to Dress Like Jodie Whittaker's Doctor

Doctor Who: Twice Upon a Time premieres on Christmas Day on BBC and BBC America.

Source: Radio Times