PHOTO BY MIYA MIZUNO / CTMG, INC.

All zombie movies deal explicitly with death. The better ones consider how our relationship with death changes in a world under existential threat. Few, if any, tackle the subject more deeply than “28 Years Later,” a sorrowful and frenetic film from director Danny Boyle and writer Alex Garland.

Any good zombie movie, you see, forces haggard characters to consider the parts of themselves that fade away when survival becomes the only mission. But only “28 Years Later” has one such character build a towering memento mori out of the bones of the dead, using it as both a monument to lives lived and a lesson on the great span of eternity.

I expected to be thrilled and scared. I was surprised to be so thoroughly moved.

Boyle directed the first film in this series, 2002’s “28 Days Later,” written and conceived by Garland; both handed their duties off to collaborators for 2007’s “28 Weeks Later.” In the intervening years, Boyle has shifted into more traditional prestige fare, creating the Best Picture winner “Slumdog Millionaire” and less lasting awards bait such as “127 Hours” and “Steve Jobs.” Garland has remained firmly in genre territory, with some sublime efforts (“Ex Machina,” “Annihilation”) and some mixed bags (“Men,” “Civil War”).

Both seem invigorated by returning to their old lurching ground. Boyle and cinematographer Anthony Dod Mantle use a tactic of controlled chaos, turning the camera into a frenetic storyteller; it’s a film relayed to the audience like a tale told by an excited narrator around a late-night campfire. We flash and cut from one place to another, from dream to reality, from history-mining montage to high-tech effects shots.

It’s a captivating, demanding approach; it will likely overstimulate some viewers. While not every choice works, those that do are indelible; in one scene, a father and son run across a submerged causeway under the glow of the Northern Lights, a hulking pursuer on their tails. Music swells; tension mounts. It’s the type of showy filmmaking that is not in fashion — largely because few filmmakers are good enough to pull it off. Boyle is.

Garland, too, works magic, crafting a tale that would be maudlin elsewhere. In the world of the film, the English mainland has been made a permanent quarantine zone, leaving survivors to fend for themselves. On an island outpost, a sort of normalcy has set in. There is no advanced medicine, however, leaving Spike (Alfie Williams) to make a desperate journey to dangerous territory in the hopes of finding a cure for his mother’s (Jodie Comer) debilitating illness.

The pair will meet up with a doctor (Ralph Fiennes) who is also the man responsible for the towering, paganistic memento mori mentioned above. The results are heartbreaking — and oddly comforting.

It is, dare I say, a work of philosophy. The zombies are just the messengers.

My Rating: 9/10

“28 Years Later” is now playing in theaters.