The teaser trailer for Christopher Nolan's Tenet has now found its way online, and while it still hasn't been officially released by Warner Bros., this is a fairly decent version.
Unfortunately, the subtitles are not in English (not that it'd make much sense even if they were!), but the footage shows John David Washington's lead examining what appears to be a flaw in some glass, most likely made by a bullet. We then get some flashes of his character in various dangerous-looking situations, and a final shot of him inhaling some kind of gas.
All we really know about Tenet's story is that it's "an action epic evolving from the world of international espionage," but this teaser would seem to suggest that there will also be a sci-fi element to the plot.
Tenet also stars Robert Pattinson, Elizabeth Debicki, Dimple Kapadia, Aaron Taylor-Johnson, Clémence Poésy, Michael Caine and Kenneth Branagh. The film is set for release on July 17, 2020.