Stranger Things season 4 VFX Supervisor, Rodeo FX's Julien Hery, reveals which VFX shots took 2 years to make. The Duffer Brothers' hit fantasy/ horror show first premiered on Netflix back in 2016, quickly developing a passionate fanbase. Stranger Things most recently returned for its fourth season, featuring more action than ever before and upping the stakes significantly. Stranger Things season 4 propelled the show to even greater heights and has broken numerous Netflix viewership records.

From relatively humble beginnings back in season 1, Stranger Things season 4 sees the show go bigger in scope and scale than ever before. While the series has always featured impressive visual effects, Stranger Things season 4 takes this to a whole new level, boasting a handful of fantastical sequences, both in the real world and in the Upside Down. As part of an elaborate plan to defeat Vecna (Jamie Campbell Bower), many of the main characters are forced to confront the villain in the Upside Down, which features vast landscapes, evil demobats, and epic action sequences. While characters have traveled to the Upside Down in previous seasons of Stranger Things, season 4 takes this to the extreme and realizes the alternate dimension on a much grander scale.

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In a new interview with Collider, Hery reveals that some of the VFX shots created by Rodeo FX for the Upside Down took a surprisingly long time to make. Hery cites the scene where the demobats fly over Hawkins and then land on the Creel House as one of the shots that took around 2 years to create in total. The VFX supervisor explains that they started working on the preliminary aspects of the shot before the pandemic hit and that when production on the show was shut down, they kept working on it, trying to perfect the animations. Check out Hery's full comment below:

"Actually, there’s a fun fact, we started before the pandemic on this show, we started to work on it more than two years ago. We actually started to develop a few looks, started to work on the assets before the pandemic. And when it stopped, we kept working on one or two shots. One is a flyover of Hawkins — to follow the bats over Hawkins, and then you land onto the Creel House. And this shot took us almost a year and half or two years of making it happen, changing the animation, and there was plenty of time, so we took like such a long time to develop that shot. So it was pretty cool."

Stranger Things season 4 Creel house bats

While Hery doesn't reveal the second shot that took nearly two years to make, Stranger Things season 4 boasts a handful of impressive CGI sequences, any number of which could have taken just as long as the demobat scene. In previous seasons, the Upside Down is depicted mostly on a smaller scale, often from the point of view of the main characters traversing it. In Stranger Things season 4, however, the world of the Upside Down is significantly more fleshed out, with the demobat sequence, in particular, showing off the creepy landscape like never before from a brand new perspective.

It remains to be seen what Stranger Things will do in season 5, its final season, but the ending to Stranger Things season 4 suggests that there will be plenty of intricate VFX shots to come. With Hawkins now ground zero for the incursion of the Upside Down into the real world, fans of Stranger Things are likely in for bigger and bolder CGI sequences than ever before. In a time where the visual effects in big blockbusters are under scrutiny like never before, Stranger Things remains a showcase of how good CGI can look when artists are given the time and resources they need.

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Source: Collider