It may be the height of summer, but have you felt a winter's chill in London this week?
Londoners were left aghast as he descended on the capital joined by his troop of White Walkers.
And after sightings at Oxford Circus, Tower Bridge and finally the Tower of London, the troupe advanced on Buckingham Palace's Throne Room.
Yes, Game of Thrones is back next Monday - and a few of its most fearsome characters have brought the Westeros winter to London.
Five actors were transformed into the infamous White Walkers, who then appeared in and around the city, bringing their deathly chill.
It took specially designed prosthetics and whole team of stylists and body paint artists to complete the look.
Their costumes took over eight weeks to create and each actor spent four hours in makeup before hitting the streets of London.
Each Season 6 episode of Game of Thrones was viewed by over five million across Sky's platforms.
The Night King setting off from Hadrian's wall is iconic because the wall inspired George RR Martin's vision for The Wall - a 700-foot wall made of ice in Game of Thrones.
Cast and crew tell what to expect from the new season
Commenting on what to expect from the White Walkers in Season 7, GOT actor Rory McCann (Sandor Clegane, aka The Hound) said: "This season everyone needs to join forces and fight the White Walkers. Because if they don't... everyone's getting it."
Isaac Hempstead-Wright speaking about his character Bran's new role as the Three-eyed Raven, said: "They are sworn enemies from the first day of time, the Three-eyed Raven and the Night King. Bran knows better than anyone the terror and fear that they should all be feeling with this threat looming over them. All that matters is the Great war."
Commenting on the show’s imminent return, Zai Bennett, Director of Programmes, Sky Entertainment UK and Ireland, said: “It may be summer in the UK, but after six seasons, winter has finally arrived in Westeros.
"With Jon Snow crowned King in the North, Cersei on the Iron Throne, Daenerys Targaryen and her colossal armada crossing the seven seas to Westeros and the Night King moving south at the helm of a truly terrifying army of the dead, the greatest battles are truly ahead of us.
"With this in mind it seemed fitting to unleash our very own troop of White Walkers on locations across the UK.”
Watch Season 7 of Game of Thrones on Sky Atlantic and NOW TV from Monday July 17 at 9pm.
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