'Doctor Who' Christmas special air date, plot rumors: Will the First and 12th Doctors time travel to the 2013 special episode 'The Day of the Doctor?'

The promotional poster of "Doctor Who" Christmas special Facebook/DoctorWho

Fans have been waiting for the upcoming "Doctor Who" Christmas special, titled "Twice Upon a Time." Aside from the appearance of the First Doctor (David Bradley), the exit of the 12<sup>th Doctor (Peter Capaldi), and the introduction of the new female Doctor (Jodi Whittaker), upcoming twists and turn of events are something fans should look forward to.

To make fans more excited, the first look into "Twice Upon a Time" was recently revealed, giving a glimpse of the classic TARDIS, Bill Potts (Bradley) and the current doctor's reunion. In one of the snaps, there is an arrow display in the background, while the hexagon wall is back.

It has been said that this is to give "Doctor Who" Christmas special the 60s TARDIS look, but this could also be implying something else. To recall, the 11<sup>th Doctor (Matt Smith) met The Curator (Tom Baker) in a place with the very same hexagon background, although the angle was a little different. 

There are theories that the two scenes might have a connection, and TARDIS has been keeping this design all along. Hence, the 11<sup>th Doctor and the original one hinted its future Curator-based design. Also, there are assumptions that it might be a visual clue that the Curator has a deeper connection to the Doctor.

In other snaps in the "Doctor Who" Christmas special, the First Doctor and The Captain (Mark Gatiss) are standing together. In another, Bradley's character looks like he is not in the mood and tired, while two TARDISes are seen in the background.

Meanwhile, Bradley's appearance in the special Christmas episode is said to be a nod to the show's 50th anniversary special, titled "The Day of the Doctor." Here, all of the incarnated Time Lords unite, including the not-yet-introduced 12<sup>th Doctor, to save Gallifrey.

Since his appearance in the 2013 special episode has never been revealed on the main show of "Doctor Who," there is an assumption that the upcoming Christmas special will fill that hole. With the return of the First Doctor, the two might go on a journey to return back through time in that particular event.

This scene could show Capaldi's first appearance and his final good-bye. Also, this is the time for the 13<sup>th and first female Doctor (Whittaker) to be introduced.

"Doctor Who" Christmas special, titled "Twice Upon a Time," will air on Monday, Dec. 25, at 5:30 p.m. EST on BBC.