There was Inception. It had a fantastic soundtrack but some moments of heavy handed exposition. However, it still managed to hide its cinematic mechanics - we still don't quite know how the characters 'go under' so to speak - and it is was all the better for that. Then came Insterstellar, which lost its way with an awkward blend of astrophysics - think giant wave - and the bookshelf and a bizarre fantastic 5th dimensional nonsense. A film that didn't quite glue together. The cinematic mechanisms splitting the film at its joints. And then came Tenet - with a compelling if underwhelming soundtrack. The cinematic mechanisms became the movie. And it so badly fell apart. In nearly every scene Nolan lost opportunties for great characterisation, dialogue and a compelling plot. His enthusiasm for the machinery of move making drowned the film. It didn't work, except in short bursts - well staged backwards/forwards sequences. The rest was nonsense. Think about it - narrative can be disrupted but if the future retroactively causes the past (Oedipus perhaps the greatest example) the opening needs a well thought reverse narrative. Did this have one? No. If future protagonist could retroactively affect the past then why not intervene before he has his teeth pulled out? It felt like a first draft of a promising idea with lots of money thrown at it.