This item contains spoilers.
Press reaction to this year's Christmas Special, The Return of Doctor Mysterio, is overwealmingly positive with most reviewers enjoying the first new Doctor Who to hit screens this year.
"The happiest, most heroic Christmas special in years" is is how The Telegraph describes the episode with much praise going to the lead actors. "Capaldi was charismatically mercurial, switching between silliness and sadness. Nardole, who could have been a mere stop-gap until new companion Bill arrives next year, worked well as an affable comic stooge – with the added ability to put his finger on the painful truth of the Doctor’s loneliness and grief"
Praise for the actors was also abundant in Radio Times who called the episode "a beautifully packaged hour of uplifting escapism". "The scenes between the Doctor and eight-year-old Grant (Logan Hoffman) are delightful, allowing Capaldi to work some grandfatherly charm and tottering eccentricity. Canadian actor Justin Chatwin looks great as both the lackadaisical nanny and rippling Ghost, while Britain’s Charity Wakefield is lovely as his Lois-Lane-alike".
A charming and funny festive special is how Digital Spy heralds the story, with much praise for the script by showrunner Steven Moffat. "It's one of the most richly comic episodes in recent memory, employing witty wordplay, great sight gags and even a joke about Pokémon Go."
The script also wins plaudits from the Los Angeles Times. "The episode plays very much to Moffat’s strengths. He has a talent for fast-paced farce, with characters going in and out of doors and portals in space and time —the episode’s central engine, the difficulties of managing a secret identity, is a classic situation-comedy situation — and for crafting banter of both the light and glancing kind and of the kind that intimates deeper feelings below."
The Guardian appreciated the move away from the traditional, overly Christmas type of episode. "There are only scant, functional references to Christmas in The Return of Doctor Mysterio. Rather, it channels the classic 3.10pm movie of yore – specifically, the Richard Donner/Christopher Reeve Superman films. And for that, it ranks in my personal top five of Christmas Doctor Whos."
GamesRadar feels the episode sets the right tone from the start. "The pre-titles sequence is a charmer, establishing the wry, buoyant tone. Logan Hoffman’s winning as the young, comic-crazed Grant Gordon while the Doctor’s sniffy take on superheroes is good value, particularly the sly line where he wonders if Spider-Man’s radiation-imbued superpowers are “vomiting, hair loss, death”. That’s dark for Christmas."
Cartermatt enjoyed the comedy in the story. "Everything that we saw between The Ghost and Lucy was ridiculous, but also incredibly funny. The exchange where he was going to reveal his secret identity to her while she realized how amazing Grant was to her was amazing, especially when he chickened out of making the move when he realized that she admired Grant’s “honesty.”"
IGN is less enthusiastic about the story calling it an OK return for the Doctor. "Its most effective moments land with the few brief times when it connects to that tale or the Doctor’s past, with the rest of the superhero-themed segment feeling slightly detached and less relevant"
AV Club is also less impressed "On balance, The Return Of Doctor Mysterio is just about fine. It’s probably a lesser episode than The Husbands Of River Song, but it also has a better sense of its overall purpose than that episode did, which careened from cartoonish to tragic with minimal warning."
Nerdist appreciated the central theme of the episode. "The Return of Doctor Mysterio is exactly the kind of adventure story we need for a Christmas Day. It tells us we don’t need superpowers or a mask and cape to be heroic, and that the bravest thing you can do is speak your mind and stand up to the bullies of this world. That’s what Doctor Who is, and I for one have badly needed it."
Finally, Den of Geek was impressed by the directing. "Visually, director Ed Bazalgette is immediately on board with the style of the piece. His comic book-into-real-life opening was quite lovely, but also there’s the segment where he splits the screen. This is an old Hitchcock trick, of course, but when the Doctor starts to edge over the line of his split, then the comics aesthetic clearly came to mind too."
Our own review of the episode can be found in Doctor Who Reviews