As usual with Nolan, this is a film that stumbles over its own hyperbole but still is "important" because it expresses so many obsessions of today's blockbuster cinema in extremis. The action-sequence with some (human and non-human) actors moving backwards, others forward in time seem like the most extreme consequence of Bay's, Scott's and their followers' desire to crack open spacetime by means of digitally enhanced action and unbridled editing. The Transformers or something seemed to bend the laws of physics, here the laws of physics are finally totally reversed and you cannot even be sure if the bullets will fly towards the target or return to the gun.

Like all his other films, Tenet also suffers from the lack of visual imagination on the part of its director. But here, as was the case with Memento, a certain minimalism of the production design interacts beneficially with Nolan's pedestrian sense of style. The whole film is set in and around non-spaces: literally nowhere. Everything is tinted in a light shade of copper and has a metallic shininess like the freakin' Guggenheim in Bilbao. The film's universe has a thin density and it's alluded to, that it could take place in a branch of time that is about to become annihilated anyway. Maybe nothing that we see will ever have happened!
The characters are not only unstuck in time but also detached from conventional character psychology even though the film increasingly reintroduces conventional motivations in the latter half, which makes for an interesting tension between pure cyphers clashing against each other in some kind of nondescript parallel universe in the first half and remnants of realistically shaped character-arcs bubbling up like distant memories in the second.

All of this means, that I enjoyed the film quite a bit, even though its high-concept hook didn't work for me on an intuitive level. I couldn't spontaneously tune into the device of "inversion" and it didn't make much sense to me until the end. But somehow this may even contributed to my enjoyment because it felt like watching, say, a Mission Impossible movie with a glitch. Also it made me better understand the concept "mindgame film" (I think it was proposed by the late Thomas Elsaesser in relation to Nolan's films). The mindgame film is a film that doesn't rely on sequential logic so much because repeated viewings are part of the fun. Tenet rather successfully proposes a belated manifesto of the mindgame film. Like the protagonist who, at the end, is apparently about to reenter the film's universe right before its proper beginning, the viewer also will have to review the film and check if and how it all comes together. It doesn't, really, but who cares. People will make this a cult-movie anyway.