Mark Gatiss on revisiting Doctor Who's The Crimson Horror and its surprising links to Sherlock Holmes and Dracula

"I mean, even to have those things, like 'The Changing Face of Doctor Who' [a blurb printed on the first page of Target novels, identifying which Doctor was featured in the book], and I think I smuggled in a little asterisk - 'see Doctor Who: The Snowmen' or something like that. It makes me very happy indeed to have those in.

"I remember when the show came back, thinking 'Wouldn't it be nice...?' but it felt a world away. But nowadays, it feels eminently feasible that you could continue your long postponed collection after all these years. I’m going to dig mine out of the loft so I can start putting them together again!"

For any non-fan, or perhaps even a Doctor Who aficionado who wasn't raised in the 1970s, '80s or '90s, this enthusiasm might be difficult to grasp. But for a certain generation of fans, the book range published by Target between 1973 and 1994 - novel adaptations of Doctor Who TV episodes, many written by the show's former script editor Terrance Dicks - was a gateway into the wonderful world of the BBC sci-fi series.

"They were a huge part of not just growing up and learning to read, but very much part of Doctor Who when you couldn't see the old ones," Gatiss says. "And as we've opined over the years, to actually see the real ones having expected them to be like the books, it's quite disappointing sometimes! They were a magic thing in so many ways – particularly Terrance's wonderfully economical and terse style, but they're also beautiful and full of sort of wonderful pop poetry. 'Through the ruins of a city stalked the ruins of a man' [the opening line in Dicks' 1977 book Doctor Who and the Dalek Invasion of Earth] and things like that."

Twenty-four years after the last Target Doctor Who book was released, the brand was revived in 2018 with new novelisations of stories from both the classic and the revived series, with Russell T Davies revisiting his 2005 relaunch episode Rose and Steven Moffat adapting 50th anniversary special The Day of the Doctor. A second batch of new Targets were released on 11th March this year, including the first to feature Jodie Whittaker's Thirteenth Doctor – a book based on 2018's The Witchfinders, by original writer Joy Wilkinson.

As part of this new set, Gatiss was asked to translate 2013 TV story The Crimson Horror into prose and, for all his affection for the original Target novels, he was determined that his book be more than just "an exercise in nostalgia."

"They're deliberately retro, the Chris Achilleos style and everything [the books' cover artwork by Anthony Dry apes the almost psychedelic style of original Target cover artist Achilleos] but equally, as with the series itself, it's good to try and keep it going forward. So it's not entirely a pastiche of the Target style, because obviously it's a modern story. I didn't want to lose the speed of the TV story, because that's one of my favourite things about it. It's like a comic strip really, it just happens really economically, and I didn't want to slow that down by massively adding to it. So I've sort of written a prequel [detailing the character Jenny Flint's first meeting with the Doctor] and then the story happens as breathlessly as it does on TV."

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First aired on the 4th May 2013 as part of the revived Doctor Who's seventh series, The Crimson Horror saw the Eleventh Doctor (Matt Smith) and companion Clara (Jenna Coleman) team up with Silurian detective Madame Vastra (Neve McIntosh), her wife and partner Jenny (Catrin Stewart) and their alien butler Strax (Dan Starkey) – the trio collectively known as the "Paternoster Gang" – to foil a sinister plot by chemist and engineer Mrs Gillyflower (Diana Rigg) to unleash a poisonous substance across the Earth.

In preparing to write the book version, Gatiss not only rewatched the TV episode for the "first time in donkey's" but also "dug out a few earlier drafts" of his script, rediscovering story concepts along the way that didn't make it to the final story as broadcast.

"The original pitch was going to have Conan Doyle in it," he reveals "I remember I'd written Cold War [an earlier episode from the same series] and then I got a text from Steven [Moffat, then-Doctor Who showrunner] asking if I'd do another one. He wanted an episode that was almost a Paternoster Gang spin-off, with Conan Doyle – and of course I said yes!

"And then I tried – I had all kinds of things buzzing around in my head – but it was just too hard. I mean, if it was the Doctor and Conan Doyle and Mrs. Gillyflower... but with the gang as well, there's not enough for him [Conan Doyle] to do. But it left this legacy – that's why there's the optigram at the beginning, because Doyle was an eye surgeon and that's that's where all that was going to come from."

The idea to include the creator of Sherlock Holmes didn't make it past the plotting stage, Gatiss says. "There certainly wasn't a first draft with Doyle – but he does deserve his own story, so maybe one day."

The episode's "monster" too was originally supposed to take a different form, with its writer originally drawing inspiration from the Matchgirls' strike of 1888, an industrial action which saw women and teenage girls who worked at the Bryant & May match factory in Bow, London protest against unsafe working conditions, with exposure to white phosphorus leading to some workers developing phosphorus necrosis of the jaw, also known as "Phossy jaw".

"I had this idea for the monsters – they were going to be all in black, sort of like Scottish Widows! And there's this horrible condition called Phossy jaw, where their jaws would literally drop off from the contamination of the phosphor... and they would glow. I thought this is ideal! They were going to be the sort of 'mummies', as it were."

Gatiss' ideas eventually evolved into what we saw on-screen, with the chief villain role being played by the late Dame Diana Rigg – appearing opposite her daughter, actress Rachael Stirling, for the first time on-screen. "I was doing [George Farquhar play] The Recruiting Officer with Rachael at the time and I remember just thinking, 'Hello! here's an idea.' Rachel had mentioned that she and her mum had never actually worked together, so I said, 'If I wrote a Doctor Who for you, d'you think you'd do it?' and they leapt at it, so it was genuinely written for the pair of them."

He adds, with a smirk, "Steven maintains that my Mrs Gillyflower at the readthrough was better than Diana was in the show, but I'm not sure it was!"

Gatiss had reached out to Stirling shortly before Rigg passed away on 10th September 2020 with the suggestion of getting together for a book signing, but it was sadly not to be. Instead, the novel version of The Crimson Horror is dedicated to Rigg's memory. "She was brilliant, so much fun," Gatiss recalls. "That was the least I could do."

A key aspect of the television episode which has made the transition to print is telling much of the story from the perspective of the Paternoster Gang, with Jenny and Strax narrating parts of the novel – though Gatiss says this was also partly influenced by Bram Stoker's original Dracula, which was very much on his mind following his and Moffat's 2020 TV adaptation. "Having just done Dracula recently, it was a natural thing to try and tell such a Victorian story in that way, through diaries and firsthand accounts and phonograph records, from different points of view. In fact, they asked me to do the talking book and I said 'No you've got to get Catrin and Dan!' because if you can it makes sense. It's mostly from Jenny's point of view."

Though the story was originally pitched to him as "almost a Paternoster Gang spin-off" – something Doctor Who fans had long campaigned for – Gatiss says there was "never any talk" of a spin-off show actually happening on television, since "everyone was too busy to do such things", though he did reach out to Big Finish executive producer Nicholas Briggs to make sure that nothing he'd included in his Target book contradicted what they'd explored in their own Paternoster Gang audio dramas. "These things matter," he insists, with a smile.

It's clear Gatiss has enjoyed revisiting an episode that he calls "one of my favourites" for Target, but he says he has no current plans to write any more original novels – his last being 2008's Black Butterfly, the concluding book in his Lucifer Box trilogy. "It's too hard," he says. "I did actually start writing a book in lockdown. You always say, 'Oh, if only I had six months off!'... but I couldn't do it. It just kept getting infected by the virus in the sense that it's a sort of murder mystery and it was supposed to have a very light touch, and it just got bleaker and bleaker. I just wasn't in the right place for it, so I abandoned that.

"You must be very kind to yourself at the moment, and equally happy if you have a good day. I'm having a good writing day today. It's just alright, it seems to be working. But I said this to Steven – a global pandemic is not conducive to the muse. It actually makes you feel frightened, and uninspired actually.

"I shot my ghost story [an adaptation of MR James' The Mezzotint for BBC Two] last week, which was wonderful, but it was like nine months worth of human interaction in five days. I was giddy and exhausted, just from thinking so much, you know? But it was great. Nice to feel something's happening, anyway."

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He's keen, though, to continue to embrace the new Target range of Doctor Who stories, whether as a writer or just as a fan. "Some of them immediately occur more than others. I think I'd like to do Empress of Mars as a full-on Brian Hayles sort of Target – that would be nice, wouldn't it? They present different kinds of challenges, depending on what sort of style you're going for.

"But I'm so glad they're doing them and I really hope other people get to do more, because it is a lovely thing. I'd like to go on a long holiday when all this is over and take half a dozen new Targets. Really enjoy myself!"

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Doctor Who: The Crimson Horror is available to buy now as part of the Target Collection, along with Dalek by Robert Shearman and The Witchfinders by Joy Wilkinson.

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