You need to watch the best zombie thriller of the century on HBO Max ASAP

Any good zombie movie plays on the thin line between human and monster, and you only have until Halloween to watch the one that does it best.

28 Days Later opens with scenes of horrific violence (a man being hanged by a crowd, mount-mounted cops beating protestors).

An extremely economical opening sets up the plot. The attempt to “cure” humanity’s violent impulses in a British lab unleashes what comes to be known as the Rage Virus.

Anyone inflicted with Rage (marked by their red eyes) has an irrepressible desire to kill. It doesn’t take long for all of England, where the film is set, to collapse.

One of 28 Days Later’s protagonists, Jim, awakens alone in a hospital, oblivious to how the world has fallen apart during his stay.

To get these impressive shots of the city without a soul in sight, 28 Days Later’s crew shot just after dawn for minutes at a time, using digital video instead of bulkier film cameras to speed up the process.

After Selena and Jim meet father and daughter Frank and Hannah, the group heads for a military outpost that’s sending a recorded message out to gather survivors.

One of those chiller scenes shows an extended shopping trip with an upbeat soundtrack as the group stocks up on supplies.

The Rage Virus doesn’t wait until its victims die to take hold. They’re living people, and filmmakers cast athletes to portray its highly mobile zombies.

Maybe because it set itself so far apart from its inspirations, 28 Days Later helped kick off a revival of zombie horror, along with the equally subversive Shaun of the Dead a few years later.

Despite that — and writer Alex Garland taking inspiration from Resident Evil — he and director Danny Boyle say 28 Days Later is about the apocalypse, not about zombies.

The infected fall out of focus in 28 Days Later’s third act, which is more concerned with the horror people and the artificial power structures we build can inflict on others.

28 Days Later is a tense, brutal horror film, and an equally effective piece of political allegory, where human cruelty is as terrifying as any movie monster.