Throughout the years, Metallica has managed to remain heavily invested in metal while earning devoted fans outside of 17-year-old Nietzscheans and Eastern European satanists. Their 1983 debut, “Kill ’Em All,” won them their angry, head-banging base, but through the 80s and early 90s, a string of minor masterpieces like “Master of Puppets,” “Metallica (The Black Album),” and “Load” helped spread their proggish brand of thrash throughout American suburbia and beyond.

After putzing around with old garage tracks—some great covers of Blue Oyster Cult and Bob Seger are mixed in there—they took a downward spiral into Napster-hating, rehab, and the unforgivably abysmal “St. Anger”. (Remember that movie about the making of “St. Anger,” “Some Kind of Monster?” It’s kind of like watching a documentary about your house burning down.)

“Death Magnetic,” their long-awaited ninth studio album, strikes off for different ground. Yes, it harkens back to Metallica’s good old days, but it also carries the band farther into death metal than they’ve ever been before. Which is to say, “Death Magnetic” is one of the most experimental, lush albums you’ll ever find that has anything to do with death metal.

Even when the tempo grows intense and threatening, the sonic texture stretches back through layers and layers of guitar and bass, underscoring the vast canvas of Lars Ulrich’s drum set. Newcomer Robert Trujillo is the rare bassist who can keep up with both Ulrich’s punishing tempos and Kirk Hammett’s roaring guitar solos. Slayer and Anthrax may have their own fiefdoms in the thrash pantheon, and System of a Down may manage to retain their composure when they swing over into metal, but at their best, Metallica plays with more deliberate sophistication than any band that’s ever shred.

Fanboys will no doubt note that “Death Magnetic” is Metallica’s first collaboration with Rick Rubin, the legendary producer behind Slayer and System, among others; his influence lends the album its spare, deathly tint. But even as James Hetfield’s lyrics darken, the band continues to invent itself out of its songs’ subject matter. Although Hetfield vows to kill himself in “The Day That Never Comes” (“Love… is a four letter word / Here in this prison / I suffer this no longer / I’ll put an end to this, I swear”) Hammett’s closing solo echoes the eerie opening melody, and nostalgically recalls “Fade to Black” off “Ride the Lightning,” almost washing away the grime of suicide.

In “All Nightmare Long,” the most fun and traditional song on the album, Hetfield chants, “Still life… / Immolation / Still life… / Infamy / Hallucination / Heresy.” But the band is just so happy to be tearing through a good old thrash tune that the song feels bracing and exuberant.

The result is an album whose ferocious commitment to several strains of the metal tradition belies its patent complexity and eagerness to appropriate other musical idioms. “The Unforgiven III” opens with familiar themes of Norse mythology and epic journey: “Set sail to sea, but pulled off course / By the light of golden treasure / How could he know this new dawn’s light / Would change his life forever?” But the string quartet and clutch of trombones that introduce the song, as well as Hetfield’s vividly colored lyrics, make it feel fresh. “Death Magentic” is truly a triumph for Hetfield, who—in addition to coming back from rehab and “St. Anger” with a singing voice that stays clear and bright even at its angriest—has written the best lyrics of his career.

Most strongly, though, the album feels like the band’s atonement—not only for all of their recent letdowns, but for every bum lyric or misplaced fill they’ve ever written. Such is the relentlessness of Metallica’s self-criticism. At the end of “The Unforgiven III,” Hetfield asks, “How can I be lost? In remembrance I relive / So how can I blame you, when it’s me I can’t forgive?”

—Reviewer Kyle L. K. McAuley can be reached at kmcauley@fas.harvard.edu.