This year, BBC's veteran series will take over Hall H in the Convention Center beginning at 2 p.m. local time for what will be an emotional panel field by the end of era on the show!
Steven Moffat, in what will be his last Doctor Who Comic-Con as a the showrunner, said that the episode is about both the First and Twelfth Doctors refusing to regenerate, and going on an adventure with Gatiss's unknown character (although he looks a lot like the classic fan-favorite Brigadier Alistair Gordon Lethbridge-Stewart, he isn't, which you can tell because he's wearing a uniform from World War I). It has also been confirmed that companion Bill Potts, played by Pearl Mackie, will appear.
Traditionally, the Christmas Special is used to introduce any incoming Doctor in a regeneration sequence, so we will also see Jodie Whittaker's Thirteenth Doctor for the first time.
It also seems highly likely that Jodie Whittaker will make a surprise appearance at the show's panel in order to tease her ground-breaking turn as the legendary series' first female Doctor!
The Season 10 finale left things on a massive cliffhanger that will need to be sorted for the annual Christmas episode. He'll play a WWI soldier known only as "The Captain".
It was also announced that Mark Gatiss will co-star in the episode in a guest role. America remedied that situation today, releasing a brand-new teaser trailer for the "Twice Upon a Time" episode at San Diego Comic-Con.