The famous shopping district will be recreated by 3D graffiti artists Max 'n' Joe and feature a series of classic movie props. Photos taken at the activation will be uploaded immediately to the campaign's dedicated microsite, and will be available to share on social media immediately.
Brand Warriors will be on hand to engage with passersby as they queue for their photo opportunity.
The experience has been devised to celebrate the first birthday of the Diagon Alley attraction at NBC's Universal Orlando Theme Park.
Chris Russell, managing director of Tribe Marketing, said: "As the father of three young Harry Potter fans, bringing Diagon Alley to life like this has been a brilliant experience. Our brief was to promote Universal Orlando and its Harry Potter attractions in as magical a way as possible and this activity certainly delivers.
"And what better place to celebrate than King's Cross, the starting point for so many magical adventures for Harry and his friends?"
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