The presence of a dog and a baby in the New Year’s Day episode, The Six Thatchers, is already well known. “Sherlock’s not quite as in love with babies as I am,” says Cumberbatch. “Yeah. He’s got a deep affection for it, the child. But he’s got a lot going on. He can’t stick around for nappies and mealtimes!”
And Mark Gatiss, co-creator, writer and producer with Steven Moffat (Gatiss also plays Holmes’ brother Mycroft), reveals that he personally asked to smash one of the clay busts of Margaret Thatcher that are destroyed in the episode.
But trying to prise further plot details or an update on whether this might be the final series (its last episode, teasingly, is called The Final Problem) proves impossible. “Erm, no comment. Yeah, stuff happens, what can I say? You’ll have to wait and see. Hmm, yeah, next question, haha!”
Who wants spoilers anyway? We are, however, promised more darkness than before and a new nemesis in the form of Toby Jones.
They really understand that they are essentially in our office for that moment
“Maybe this is the fourth or fifth time we’ve worked together,” says Cumberbatch. “Toby’s an old friend. And he’s at the height of his powers. He’s phenomenal. Wait till you see what he does, it’s extraordinary.”
Despite the darkness, the show’s trademark wit is still very evident. “In the most sort of precariously brilliant way. It’s just incredible how [the writers] can – and hopefully we pull it off in practice – switch tone and still keep you hooked into stuff that seems really high stakes and really dark and yet can make you laugh out loud in the same scene,” he says. “And you’re right, that is its trademark. It’s definitely not going to be losing its humour.
“The relationships are more detailed, stronger, more explored than they’ve ever been,” he continues. “And there’s great darkness in some of that, and also utter brilliance and light and love and goodness.”
After the interview, Cumberbatch will join his cast mates for a night shoot on North Gower Street. “We’re doing stuff outside. Leaving and entering 221B. Or at least, I am. I can’t remember what everyone else is doing. I do read the scripts and then I just focus on what I’m doing – because it’s quite a lot. They artfully don’t write too much that’s too difficult,” Cumberbatch explains of these London street scenes.
The friends that I’ve made as part of this fandom have honestly changed my life
Habitually they attract crowds of hardcore Sherlock supporters eager for a hit of live action. These are the fans who drive the show’s frenzied following. Is it special filming in front of the fandom?
“Special is the word for it!” laughs Cumberbatch. “It’s very special. It’s a bit bizarre but they’re very benign. It would be a lot worse if they were throwing rotten fruit. Who knows? That might happen tonight. They might be furious with everything that was in the Christmas special last year.
“But, by and large, they’re an incredibly respectful crowd. They’re a home team, home crowd. They really understand that they are essentially in our office for that moment. More so than a drunk passer-by. That’s more difficult than 400 ardent fans. It’s pin-drop quiet when we’re doing a take.”
Cut to the night shoot on North Gower Street. The street signs switched to Baker Street the previous evening. Word spreads quickly through online communities. By mid-morning, hundreds of Sherlock fans are in position behind barriers as the crew prepare rain machines, lighting rigs and ensure no shrines to Cumberbatch and co are visible to the camera – that would be too meta, even for this show. Over the next few hours, while The Big Issue meets Cumberbatch, Martin Freeman and the rest of the cast in a nearby hotel, the crowd of Baker Street regulars swells.
I’m walking into this world that means so much to so many people
How do they know where and when to come? #Setlock is the hashtag that guides fans towards filming sites across London, Cardiff and the wider world, and it seems Sherlock Holmes is not the only detective with a vast street team helping him out.
“The most important part is the community experience,” explains superfan and blogger hotsmugstache, 21, from London. “The other big part, of course, is the game. It’s the real, hard detective work of finding locations and analysing what is being filmed.
“Even with all the information we gain from this really quite meticulous work, we still are nowhere near able to tell too much about the final plot of the series. In some ways we get the enjoyment of revelation twice. It doesn’t spoil anything for me.”
Last summer hotsmugstache decamped to Cardiff for five weeks and also enjoyed a close-up view of the action in London. “Some of the best and let’s say extreme experiences were the night shoots. I have stayed up all night standing outside at the set from 6pm to 8am for the complete duration of a night shoot,” she says.
Leslie, AKA thesetison, is 21, an active participant since 2014 and compiler of what she describes as an online #setlock compendium. Based in Virginia, USA, this is fandom at a distance – but no less intense.
“Having someone online watching more information come in is really helpful to the people who are actually out looking because I can message those Setlockers and point them in the right direction,” she says.
“The friends that I’ve made as part of this fandom have honestly changed my life,” she continues. “I know people all over the world because of it. There are 12 people currently planning to come to my flat so we can all watch the series four finale together, some of them flying in from literally thousands of miles away for it. Obviously it all started with the show – that’s what brought us to this fandom in the first place – but we’ve stayed because of the people we’ve found here.”
As darkness falls and the lights come on, the cast arrive. Now, the game is on. Huge whoops greet Martin Freeman. Amanda Abbington wanders over to chat to fans. There is no jostling, no pushing. An assistant director reminds them people live around here: “It’s great that you’re here today but remember it is a residential place. No more whoops and screams, thank you so much.” Excitement mounts. Cumberbatch is on his way. He arrives. In full Sherlock costume. The sound is uncanny. Excited silence. A deafening vacuum as fans on all corners of the surrounding streets silence themselves, hands over mouths.
No other show, even ones whose audience is similarly gargantuan, has fans like this. Not Doctor Who, not GBBO, not Call the Midwife. Arrive at Elstree Studios any day of the week and a few hardy EastEnders fans are there but it is hardly Beale-mania.
Alexis, 19, takes her eyes off the show’s star for a minute to talk to The Big Issue. “I love Benedict Cumberbatch,” she declares. “We are big nerds, and proud of it.” Kathleen, 21, nods in agreement. Another fan who has travelled from Paris is staying to watch the filming all night before returning on the Eurostar in the morning. Nurses in the halls of residence next door to Speedy’s Cafe lean out of top-floor windows, getting perhaps the best view of the madness.
Director Rachel Talalay has already had a taste of hardcore fans, working on Doctor Who. She agrees, though, that Sherlock is on a different level. “First and foremost, my fear is the responsibility of following such brilliant work,” says Talalay, who makes her Sherlock debut with The Six Thatchers. “But also, the show has such passionate fans. So I feel a massive responsibility to the fandom. I’m walking into this world that means so much to so many people.”
Martin Freeman breaks into a broad grin when the fans are mentioned. “We don’t write the show just to please people who are fanatical about the show but to pretend those people don’t exist would be crazy,” he says. “I have never known anything like – I’m 44 but I’m saying the word ‘fandom’. Fuck it! – the fandom of this show. But at the same time that’s not the 12 million people who tuned in at Christmas. They’re not all like that. Most of them are your uncle or my cousin. And you have to do it for them, while doing enough detail to please the people who know it way better than I do.”
Cumberbatch adds: “It’s sometimes a bit weird and confusing to know you can’t really be off. Literally, if you trip up or if you raise an eyebrow, it becomes an internet meme,” he says, raising an eyebrow. “That’s a bit weird. You just have to turn a filter on in your brain. Sometimes I’m good at that, sometimes I’m not.”
Sherlock series four is on Sundays, 9pm, BBC One