Matt Hurt’s review published on Letterboxd :
Cuarón's Children of Men is a bona-fide masterpiece of science fiction and another impeccable feat of filmmaking from him and cinematographer Emmanuel Lubezki. The world this film resides in is one of the bleakest futures I've seen depicted.
Part of the magic of this movie is in the world-building. It opens with a news report stating the "youngest person on the planet" was killed in a bar fight at the age of 18. Theo (Clive Owen) watches the news in a coffee shop with shocked patrons in mourning. He gets his coffee, steps outside, and begins pouring scotch in it when an explosion is set off in the coffee shop. In the ensuing chaos, we see a woman walk out of the shop carrying her freshly severed arm. All of this takes place in one take and it's as visually mesmerizing as it is informative of the world we've stepped into with Theo.
Children of Men bludgeons the viewer with its horrific view of the future. There's an incredible line about halfway through the film where Miriam (Pam Ferris) says "As the sound of the playgrounds faded, the despair set in. Very odd, what happens in a world without children's voices." This line is spoken in a rundown school that's been unoccupied for years after Miriam tells Theo heartbreaking accounts of her experience when humans began losing the ability to reproduce. This encapsulates the tone of the film very eloquently as we go from scene to scene filled with violence, despair, and the total absence of a future.
In a weird way, the beauty of Children of Men is that it's relentless in its despair. Even when something good happens in this world, it causes just a brief (though, breathtaking) respite from the horrors of the world. We see everyone and everything stop in their tracks, in the middle of absolute chaos, to witness something truly miraculous only for everything to resume once the moment has passed. It's a very powerful moment that leaves us wondering if Children of Men's world can ever be salvageable.
As I said before, this film is positively gorgeous. There are breathtaking sequences that are among the most intense scenes I've ever seen. Much like a lot of Cuarón's other work, I am always left wondering how on Earth it's possible for certain moments in Children of Men to be completed. It's a testament to his genius as a filmmaker and makes the movie one of my absolute favorites.