Sequels are always tricky. The original is a creative leap; the follow-up is likely to be incremental. Until now, Taylor Swift has switched up her collaborators and general sound with each album. But she has rightly billed “Evermore,” her surprise-release ninth album, as the “sister” to the one she released less than five months ago, “Folklore.”

“It feels like we were standing on the edge of the folklorian woods and had a choice: to turn and go back or to travel further into the forest of this music,” Swift wrote in a statement. “We chose to wander deeper in.”

She continued writing songs with the “Folklore” brain trust of producers and musicians — primarily Aaron Dessner of the National, who plays most of the instruments and collaborated on 14 of 15 songs. Swift’s boyfriend, the actor Joe Alwyn, had a hand in three songs under the pseudonym William Bowery; Jack Antonoff, who also wrote with Swift on “Folklore,” worked on two.

“Evermore” clings to the acoustic-Minimalistic palette of “Folklore,” with homey piano and imperturbable guitar patterns. Swift and Dessner enlisted more backup musicians for mini-orchestral arrangements by Bryce Dessner, also of the National, but for most of “Evermore,” Swift turns even further inward, away from her pop past, than she did on “Folklore,” drifting toward elegant but cerebral craftsmanship.

On “Folklore,” Swift decided she could set aside autobiography to tell stories that weren’t necessarily her own. “Evermore” features more character studies and role playing, as she sings about infidelity, con jobs, even murder. “Ivy,” written with Aaron Dessner and Antonoff, is a folky, convoluted song about a married woman’s secret affair, enfolded by banjo and guitar picking as she sings about the temptation that tears at her: “Your touch brought forth an incandescent glow/Tarnished but so grand.”

In “’Tis the Damn Season,” the singer visits her hometown for the holidays and suggests a weekend fling with someone she had left behind. In “Champagne Problems,” the narrator turns down an earnest proposal, singing, “Sometimes you just don’t know the answer/Til someone’s on their knees and asks you.” The music is an elaborate, evolving sigh, starting with low-fi, oompah piano chords that grow entwined with guitar arpeggios and a choir of “aah”s. Swift has more fun with “No Body, No Crime,” joined by two of the sisters in Haim, Este and Danielle, singing about cheating, revenge and unsolved murders and egged on by a yowling harmonica.

Swift’s latest breakup songs, her longtime specialty, seek maturity by stepping back. Churchy organ tones surround her as she faces the end of a seven-year romance in “Happiness,” slipping toward anger — “I hope she’ll be a beautiful fool/Who takes my spot next to you” — but determined to be fair: “There’ll be happiness after you/But there was happiness because of you too.” And the album’s title song, “Evermore,” looks back, over a serene piano line, on how she used to believe “that this pain would be for evermore”; Bon Iver (Justin Vernon), returning after his appearance on “Folklore,” arrives midway through to recall more turbulent times, but Swift is determined to put pain behind her.

Swift can still bristle, as she does in “Closure.” With insistently clattering percussion and electronic creaks behind her, she refuses to give an ex the satisfaction of pretending to be amicable. Even though “It’s been a long time,” she sneers, “Don’t treat me like some situation that needs to be handled/I’m fine with my spite and my tears.” It’s a glimpse of what Swift might call “the old Taylor,” still in close emotional combat.

“Closure” is in an unconventional meter, 5/4; so is “Tolerate It,” in which Swift’s character is a woman giving her all to someone who takes her for granted. Those are two of the album’s countless musicianly flourishes, along with the restlessly intertwined guitar picking in “Willow” and the glimmering electronics and furtive pizzicato strings in “Marjorie” (which pays fond tribute to Swift’s grandmother, Marjorie Finlay). The sonic details of “Evermore” are radiant and meticulous; the songwriting is poised and careful. It’s an album to respect. But with all its constructions and conceits, it also keeps a certain emotional distance.

Taylor Swift
“Evermore”
(Republic)