For the uninitiated, Idles are a monumentally powerful British hard rock band whose music is loaded with punk and hardcore influences, although it’s not accurate to label them as either. Their songs can sound deceptively simple on the surface: They’re often based around a basic rhythm or a two-or-three note riff — or a single, bent chord — but the band can be plenty complex when they want to, and their towering, effects-laden guitar sounds owe as much to Sonic Youth and Big Black as any punk forebear.

But most of all, it’s Joe Talbot’s blow-your-hair-back vocals that give Idles their trademark: Possessed of a gravelly, overpowering voice, he roars his way through songs with titles like “Car Crash,” “War,” “Rottweiler” and the awesomely titled “Never Fight a Man With a Perm.”

While there’s enough rough stuff to please the faithful on “Crawler,” their fifth album in as many years, the band is clearly moving toward something different: It’s darker and moodier than much of their previous work, and even contains what could kind of be considered a ballad, the slow and echo-laden “Beachland Ballroom” (which the band performed on “Jimmy Kimmel” earlier this month).

But they’re easing in the new vibe gradually, and the album has masterful pacing, possibly due in part to its co-producer, hip-hop vet Kenny Beats, who’s known for his work with left-field rappers like Vince Staples, Slowthai and Freddie Gibbs (although there’s absolutely nothing hip-hop about this album except maybe some attitude). It starts off moody and ominous with “MTT 420 RR” before delivering a faceful with the piledriving “The Wheel,” eases back before peaking again with the driving, almost new wavey “The New Sensation” and the adrenaline blast of “Car Crash,” and closes out with the 30-second “Wizz” — as bruising a jolt of hardcore as they’ve ever done — followed by the hard-grinding “King Snake.”

Anyone who’s seen this powerful band live knows how quickly they can work a crowd into a frenzy — as they did on a rampaging U.S. tour that just concluded. But with “Crawler,” they’re breaking breaking rank, changing up their style without redefining it — what might come next is wide open.