The newest offering from the Boston-based trio Helium reveals a more cheerful Mary Timony at the helm. While earlier albums Pirate Prude and The Dirt of Luck cemented Helium’s signature brand of darkly menacing pop, Magic City is imagination gone wild, containing fairy tales and fantastical songs about space travel and unicorns. While Timony continues to invoke dramatic childlike personas in all her lyrics, to the point of sounding nursery-rhymish, her method is slowly maturing into a folk style somewhat reminiscent of ’70s neo-Renaissance songstresses such as Sandy Denny and Maddy Prior. Characters magically emerge from songs with titles like “Aging Astronauts,” “Cosmic Rays,” and “Lady of the Fire.” In “Clementine,” the heroine meets with a ghastly fate: “It’s the season of the witch and the drinking of wine/The seizing of the Bitch, bionic in crime/Shed a tear for our darling Clementine/Thrown in the ocean, drowning in the brine.” The generous use of keyboards and synths on the record heightens the fantasy/science fiction element, especially on the instrumental track “Medieval People,” featuring bassist and Polvo principal Ash Bowie, wherein a calliope-ready jig is accompanied by dubs of industrial explosions. “Revolution of Hearts” recalls the lyrical exuberance of The Dirt of Luck, but a midsong break into a heady synth/guitar jam pays homage to a new wave ethic à la Talk Talk or (dare it be said?) A Flock of Seagulls. Co-producer Mitch Easter provides much studio gimmickry, but the special effects are, for the most part, tastefully done. By the end of the record, you might be pleasantly surprised to discover that you’ve been listening to a fantasy opera, not a rock album at all.—Amy Domingues