Since the rise of the VR started again a few years ago, documentarians have been flocking to the medium as a new way to tell stories, albeit with mixed results.The output has ranged from well-intentioned but dull 360-degree views of refugee camps and other forsaken places, to much more immersive, nuanced and moving content, such as "The Last Goodbye." But the release of Zero Days VR, produced by Scatter and based on the 2016 documentary by Alex Gibney, has the potential to move documentary VR forward in a whole new way.While the Zero Days VR experience is based on existing content, the viewer doesn’t need to be familiar with either the documentary or the story of the Stuxnet virus to enjoy the piece. In fact, it’s almost better that they haven’t seen the original -- I had seen the documentary and there were a few points where I felt like I was simply rewatching it. However, those were far outweighed by what the VR piece added to the experience -- a sense of true immersion rather than one of removal.For one, being in the headset forces you to completely engage -- something that flat TV can’t do in the age of smartphones and tablets. When I watched the original film, there were plenty of moments where I listened to the voiceover, but skipped looking at the animated visuals in order to check Twitter or a baseball score. Whereas in the headset, I was forced to absorb them completely. They were also much more moving -- when centrifuges explode on the flat screen, there is still a sense of it happening at a distance, whereas in the headset, they burst into confetti all around you.https://www.youtube.com/watch?v=_nhIxoSwJqAScatter is one of the most highly-regarded VR shops around for a reason. They know how to strike the perfect balance of having something to look at no matter where you turn your head without being overwhelmed by too much noise. Scatter also understands when to direct the viewer’s attention. In the third chapter of the experience, an actress who plays the role of the informant looks at you while she speaks, then looks away when she describes more intense parts of the virus’s creation; it conveys a realistic sense of intimacy.Zero Days isn’t perfect -- the whole experience is a little on the long side, and might have been better as a series of pieces. It is possible to view it chapter by chapter, although it’s not terribly intuitive to figure out how to do that.Still, the overall experience is compelling and demonstrates new possibilities for documentary VR. Visuals built in a game engine can be just as compelling as footage that was shot live. And given that so many places can be hard for camera crews to access, the game engine approach can allow more stories to be told. Users can also guide themselves through the experience while still coming away with the message the director was hoping to get across -- they don’t need explicit hand-holding or direction to do so.The next logical step for this would be to create a documentary based on entirely new material, rather than an existing source. Though that’s bound to happen very soon. Once it does, we’ll be one step closer to realizing the fully transformative power of documentary VR.