DOCTOR Who fans had a lot of questions as the trailer for Jodie Whittaker's last ever episode was revealed today.
The feature-length episode will be called The Power of the Doctor and sees the return of several of the series' big characters.
It's the last of three specials this year before Ncuti Gatwa takes over as the Doctor next year and will air on October 23.
But as always with Doctor Who trailers, it offered up more questions than answers.
Among them was a brief moment when we see the TARDIS spinning through a shot - but with its famous signage looking very different.
Instead of a white panel reading: "Police Telephone: free for use of public" it was the word "HA" written in different sizes.
One fan asked simply: "WHAT IS THIS."
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Another replied: "Could potentially be Morse Code. Tried decoding it but not getting much from it."
One other suggested: "Probably something to do with the Master and his evil laugh."
Indeed, thanks to information released by the show we do know that the Master makes an appearance opposite Jodie's 13th Doctor.
The character, most recently played by Sacha Dhawan, will appear alongside other favourites including the Daleks and the Cybermen.
Fans were excited by the new trailer, with one writing: "Speaking as someone who hasn't liked this era, this honestly has me hyped as hell! Fair play!"
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Another wrote: "This looks like a great episode for Jodie’s finale! I’m so pumped and glad we have an air date now! Bring on October 23rd!"
A promo for the episode revealed the cast alongside a series of other questions.
It read: “Who is attacking a speeding bullet train on the edges of a distant galaxy? Why are seismologists going missing from 21st century Earth?
"Who is defacing some of history’s most iconic paintings? Why is a Dalek trying to make contact with the Doctor?
"And just what hold does the mesmeric Rasputin have over Tsar Nicholas in 1916 Russia?"