Even by Marvel’s standards, Doctor Strange is a super-sized production.

Most of the film was shot at Longcross Studios in Surrey, where the crew painstakingly constructed 21 sets, including a Hong Kong street (complete with over 80 neon signs and a giant roof to keep the rain out) and Doctor Strange’s Sanctum Sanctorum, which took five artists 10 months to design.

However, director Scott Derrickson decided Kathmandu’s ancient temples couldn’t be faked. So last November, he and Benedict Cumberbatch jetted out to the capital of Nepal – and it didn’t disappoint.

“I’ve been all over the world, but there’s no place on the planet like Kathmandu,” says Derrickson. “It is a city with almost no Western influence in it. It is a large city that is so deeply mystical and religious in all operations, and in a most peaceful, beautiful, colourful way. The visual qualities of that city are unlike any place else.”

Sadhu (holy men) in the Pashupatinath Temple

The first scene was shot in Pashupati, home of Pashupatinath Temple, a famous Hindu temple on the banks of the Bagmati River in Kathmandu. There were 300 extras, made up of locals and tourists, along with cows and dogs. The production had an audience of curious locals, as well as the many families of wild monkeys that freely roam Nepal.

Cumberbatch was also smitten. “Kathmandu was absolutely vital to this film, I think not least because it’s so based in something that is exotic,” he explains. “It was a magical way to start the shoot. It’s important to a film like this – which has a profound gearshift into a spiritual and otherworldly dimension – that the portal for that be in a place that actually happens in itself – regardless of the Marvel cinematic universe – to be incredibly spiritual and marvellous.”

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By the fourth day of shooting at Patan Durbar Square, they had a large crowd of Benedict Cumberbatch fans who had followed them there. Patan Durbar Square is a Unesco World Heritage Site that was badly damaged in the 2015 earthquakes. There was a crowd of hundreds shouting Cumberbatch’s name, who went wild when he waved from a building overlooking the square.

Patan Durbar Square is situated at the centre of the city of Lalitpur, one of the three Durbar Squares in the Kathmandu Valley

If Cumberbatch had hoped to escape his celebrity, he didn’t let his disappointment spoil the moment. “Being in Kathmandu with an entire film crew was astonishing, and kept on surprising me,” he says. “These beautiful places that you’d be lucky enough to get to as a traveller, let alone call it working, and then to watch that sunset over Boudhanath Stupa after a day of filming. That was perfection, really special, and tied the whole experience together for me. It was a brilliant footnote at the beginning of this long journey.”

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