Herb Gallow’s review published on Letterboxd:
Christopher Nolan has completed the journey up his own asshole. This was a subpar spy movie with the patented Nolan faux-intellectualism smeared all over it. Unlike previous products like Inception (a decent heist movie at heart) and Interstellar (an all right sci-fi movie underneath), Tenet isn't even a good action movie after you sift through all of the internally inconsistent applications of reverse entropy or whatever the hell Nolan thinks he's trafficking in.
The only actor here that seems like he cares about being in the movie is Robert Pattinson, playing the hero's sidekick. Apart from him, people are sleepwalking through this production, which is inexcusable for something with a $200 million budget. John David Washington, who had genuine charm in BlacKkKlansman, painfully delivers corny 007 quips and unconvincingly sells an inexplicable attraction to the villain's wife. Kenneth Branagh plays a character that was a squat and an Adidas tracksuit away from a Russian caricature, and plays it without any menace at all. Elizabeth Debicki is a woman in peril who can't garner an ounce of sympathy. They've all been beaten senseless by the script, which is full of terrible dialogue and embarrassing contrivances.
Overlong, stuffed to the breaking point with gratuitous battle scenes and explosions, nobody in the movie to give a shit about, and way less smart than it thinks it is. Nolan has now taken his place as Michael Bay for people who think they're too good for Michael Bay.