Josiah Morgan’s review published on Letterboxd:
One of the more astonishing formal elevations of a pure-dreck screenplay in recent years.
The tone and craft primarily echoes Soderbergh's Haywire with regard to the focus of action, explicit nature of much of the first-person violence, as well as the relatively pared down aesthetic. Indeed, it seems part of a string of recent films determined to push against the contemporary wave of high-thrill no-consequence formal decisions kickstarted by the Nolan trilogy and solidified in the recent MCU entries. At least three separate action sequences (the motorbike, the clone fight, the final fight) are among the best individual sequences in an action film since Miami Vice.
What makes the film unique in the first instance is the way it often avoids moments of impact, cutting away from action in a film explicitly tied to brute force. What makes the film unique in the next instance, and in the sense that everybody is talking about, relates to the 3D High Frame Rate. I'm not sure I've ever seen 3D this good, though the last time I saw a 3D movie must have been Lee's own Life of Pi years ago, so I may not be the best judge of this.
But there's an overriding sense of a return to the fundamentals of silent cinema here. Lee in interviews has spoken about the function of 3D is that it allows the imagemaker an extra axis with which to play: this is utilized here as both mirrors and motion always happens on the z axis as opposed to the x and y axis. In the first scene in which Smith confronts himself, an integral conversation takes place at opposite ends of a twisting staircase; the z axis provided by the 3D photography allows the audience to interpret geographical space in a more coherent manner than the majority of action films. It means that when things kick into gear they can happen faster. This z axis narratively also operates as the arena in which Smith remembers his past years; an early flashback operates within the sensation of being pulled up and down (and is complemented by an astonishing use of colour and shadow) along the z axis whereas later sequences frequently allow us to see the clone only within mirrors Smith is looking at i.e. as representations of himself, not actually as himself.
The action sequences frequently end or involve these mirrors being smashed and the destruction of the z axis. It's a fascinating film and one that seems a likely candidate for a future cult classic. The material is godawful. Lee is a true master.
Postscript: this film operates incredibly in a similar structural manner to Stephen King's 2019 The Institute, which is curious because the narrative and use of genre itself also echoes.