Not that Coleman and Smith remained incognito for long. “Nice costumes!” they screamed out of the car window at one middle-aged couple dressed as the Doctor and Clara, their characters from the series. The man didn’t recognise them, but “Clara” did, and appeared to start convulsing on the pavement. “The most embarrassing thing is that the traffic is so bad that you don’t go anywhere,” says Coleman. “So all you can do is sit there and put the window up.”
Comic-Con was Coleman’s first proper exposure to the fanaticism of the Whovians. She had never watched Doctor Who before she became the new “companion”, but the responses to her performances have been effusive, bordering on obsessive. Doctor Who blogs – of which there are legion – praise her as quick-witted and independent yet vulnerable, and are particularly taken with the flirtatious relationship she has with Smith’s Doctor – a spark that was absent with his previous companion Amy Pond, played by Karen Gillan. Or, as Matt Smith himself put it: “Clara’s different from Amy. He has more chance of snogging Clara.”
While Coleman knew Doctor Who inspired extreme passions, it had not really hit home until Comic-Con. “I was always asked how I had found the fans, but I’d just been filming in Cardiff,” she says. “At Comic-Con it was amazing to see how far-reaching it is. I thought I’d be overwhelmed, but I was humbled. It’s something that Matt says: the star is the show.”
That maxim is more obvious than ever this year as Doctor Who celebrates its 50th birthday. The centrepiece is a 75-minute special on 23 November called the Day of the Doctor, which was shot in 3D and will be shown on BBC1 and in 400 cinemas across eight countries. The episode will bring together Smith and Coleman with some of their predecessors, including David Tennant and Billie Piper, and introduce a new “dark” Doctor, John Hurt.
After that, Smith will be hanging up his bow tie and vintage Harris Tweed jacket in the Christmas special. The speculation over his successor, which shared a hysteria in common with the announcement of a new pope, ended in August when Peter Capaldi was unveiled on primetime television as the new pontiff – sorry, 12th Doctor. Coleman only found out herself a short time before the rest of us.
“They told me and Matt when Prince Charles and Camilla came to the set,” says Coleman. “We were both: ‘Ahhh, of course.’ It takes you a few moments – I don’t think he was on any of the original lists. People were talking about Rory Kinnear and people like that, but as soon as you say it, you’re like: ‘Of course.’ As Steven Moffat [Doctor Who‘s lead writer] said: ‘He’s the Doctor.’ And it’s brilliant that we’ve gone so different from Matt.”
Smith’s final appearance, however, will clearly be a wrench. “I just read the script the other night,” says Coleman. “I’d been putting it off for ages and ages, because once you read the last page, that’s it, the story is over. So I read 10 pages on the tube and I stopped, and then I picked it up again the other day and finished it. I was an absolute mess, an absolute wreck. But it’s good; it’s sad, but it’s what needs to happen. It’s perfect.”