The Doctor enlists the aid of Trev, a security worker at the hotel, as he investigates a man holding a briefcase that he is handcuffed to.

Trev's Silurian manager arrives in Joy Almondo's room at the London-based Sandringham Hotel in 2024 with the briefcase, with the Doctor following.

The briefcase is about to disintegrate Joy, when a Doctor from the future arrives from the Time Hotel and gives the override code.

A year later, the Doctor re-enters the Time Hotel and gives his past self the code (obtained by the bootstrap paradox), then departs with Joy.

They open a door to 65 million years ago, where the Doctor frees Joy from the briefcase by provoking her anger at Partygate, when she was unable to be with her mother when she died on Christmas Day due to COVID-19 lockdowns.

The briefcase reveals itself to be made by Villengard, a weapons manufacturing company with plans to detonate a "star seed" to use as an energy source, using the hotel's time travel to allow it to grow in the past.

When Davies realised he was too busy to complete the script, he shelved it and asked Moffat to write the Christmas episode instead.

So they have built extensions into more or less every hotel room in history, and you get access to it occasionally.Half the script had been completed before Davies informed Moffat that Ruby Sunday would not appear in the special.

[7] The story further explores the "Villengard Corporation", a recurring fictional antagonistic company that has been mentioned in a number of Moffat's Doctor Who episodes.

[8][9] It is the ninth Doctor Who Christmas special to be written by Moffat who once again assumed an executive producer role during production of the episode.

[17][18] Historical figures Edmund Hillary and Tenzing Norgay were depicted at a 1953 Mount Everest base camp by Phil Baxter and Samuel Sherpa-Moore, respectively.

[20] Peter Benedict and Julia Watson appeared as Basil and Hilda, guests at the Queen's Hotel in Manchester during World War II.

The Mesozoic Era room was built on a gimbal that allowed the set to tilt to give the effect that it was being eaten by a dinosaur.

The top of the Orient Express set was built in front of a green screen and placed on rubber tyres to allow the special effects team to replicate the look of a moving train.

He further elaborated by saying that "there's something here for all generations to enjoy" and praising the guest cast, namely Nicola Coughlan, Steph de Walley, and Joel Fry.

[31] IGN's Robert Anderson wrote that the special "masterfully blends the show's signature whimsy with heartfelt storytelling, delivering a cozy, deeply human tale about the transformative power of friendship" and that "Moffat's excellent script is central to the episode's success".

[30] The writing was also applauded by Bleeding Cool's Adi Tantimedh, who wrote "Moffat pins down the core of what makes Ncuti Gatwa's Doctor different from all his predecessors".