The Killers released “Mr. Brightside” 20 years ago and hardly anybody cared.

The dominant hits of the day were hip-shakers and party bangers whose titles doubled as bodily imperatives: “Shake Ya Tailfeather,” “Get Low,” “Stand Up” — odes to the delirious, thrilling movements that keep the party going. “Mr. Brightside” is … not that.

It’s an intense, dramatic song about the shattering experience of getting cheated on by someone you love. The lead single off the Las Vegas band’s debut studio album, “Hot Fuss,” consists of exactly one verse, pre-chorus and chorus, which simply repeat; the singer Brandon Flowers’s voice is the sardonic wail of a jilted lover who is physically ill at the thought of his girlfriend being with someone else (“Now they’re going to bed, and my stomach is sick”), and pretends that he is totally OK (“Comin’ out of my cage, and I’ve been doing just fine”) when he is obviously an absolute wreck (“I just can’t look, it’s killing meeeee”).

Yet in the intervening decades, “Mr. Brightside” — which eventually reached the Billboard Hot 100 over a year after its initial release, peaking at No. 10 in June 2005 — has become something more than a hit. It has grown into an all-purpose, inescapable rallying cry: a karaoke staple, a football tradition, a party playlist must-have, a meme. It’s a straight shot of nostalgia that, having survived that awkward interval when a song feels dated and falls out of favor, now belongs to a pantheon of modern classics that are both extremely of their time and transcend it.

If boomers gave the masses “Don’t Stop Believin’,” millennials can claim “Mr. Brightside” as the generation’s official entry into that canon: a song that gets everybody at the bar shout-singing along.