'Stranger Things' Drops Mysterious Upside-Down Hints For Fans Across the World

Looks like 'Stranger Things ' has launched a really massive marketing campaign ahead of season 4 premiere on Netflix. For instance, Empire State Building in New York City is to turn red in honour of the show.

But it looks like the illumination is just the first part of what's coming on May 26 at 8:30 p.m. ET. Nothing but mystery here, but it looks like we really have to keep an eye on New York City's iconic skyscraper at the given time.

Moreover, a similar thing appears to be coming to London, Tokyo, Sydney, Milan, Cologne, Bilbao and a handful of other cities across the world, up to Al-'Ula in Saudi Arabia. The only thing the Stranger Things Twitter account revealed about the event was that it's going to be "something big".

For every city, there will be coordinates with certain places, with fans left in the dark regarding what to expect there.

Given that Upside Down is not that friendly to us humans, the upcoming event could be pretty chilling – but it didn't stop fans from immediately checking out the coordinates and trying to figure out the puzzle.

You might as well join the frenzy if you live in one of the listed cities… or just sit back and wait for 'Stranger Things' season 4 to premiere on May 27.