British composer Anna Meredith thrillingly reinvents pop, classical and electronic music — all at the same time — on wonderful debut LP “Varmints.”

        Meredith first rose to prominence with the critically acclaimed debut single “Nautilus”, from her debut EP back in 2012. The song still opens “Varmints” and sets high expectations — it’s an inspired, inventive battle of brass, with numerous ascending and descending trumpets and trombones competing for space in the hectic mix. The brilliant, brazen melodies repeat themselves often, but they are played more intensely each time, giving the song an absolutely captivating sense of tension. It takes the slow build of classical music and condenses it into five-and-a-half minutes of strictly acoustic warfare — until a lurching synthesizer sneaks its way in by the end of the track.

        The next cut, “Taken,” is one of many hard left turns on “Varmints”. Ditching acoustic instrumentation entirely, the track instead opens with a nervous, skittering bass line over which Meredith and band member Sam Wilson harmonize beautifully. A simple “Yeah, yeah!” refrain is accompanied by wailing, out-of-nowhere electric guitars and synthesizers that create an incredibly catchy hook. All the while, however, that anxious bass line gets faster and more intense and more unnerving even as, on the surface, the song is a pleasant and well-written pop tune.

        “R-Type” is another stylistic switch, featuring a series of intense arpeggios bouncing off of each other as some excellently played live drums escalate and threaten to blow the song to bits. “Shill” exhilarates, taking rough electric guitar, glitchy synthesizers and delicate strings and throwing them at each other headfirst. Stunning lead single “Honeyed Words” builds beauty out of madness to form one of the most inventive songs from any scene, indie or classical, in years. It opens as a heap of abrasive effects piecing themselves together, only to form a suddenly poignant violin melody — but the dissonant electronics are not far behind, underscoring the main melody with a shrill screech. And the incredible “Scrimshaw” is a fearful journey through the cosmos, some childlike glockenspiel giving way to a swath of electronic effects that crystallize into the album’s most classical moment: a full orchestra playing a melody that feels like the crescendo of an hours-long symphony and not the four tense minutes that precede it.

         This sense of constant unease and tension permeates “Varmints”, but Meredith’s varied musical background prevents her from resolving said tension with any sort of simple crescendo or, in the current parlance, “drop.”

        Often, the songs change direction when confronted with a climax, but the bottled up anxiety still worms its way back in later on. Songs end without exploding, leaving the tracks, and the emotions, open-ended and the listener thoroughly unsettled. It’s an ingenious way to keep the listener coming back for more, to solve the puzzle of this mysterious album.

        It is precisely because of Meredith’s union of so many musical influences that she is able to access such potent emotional territory and make “Varmints” into an affecting experience. The buzzing sound effects and abrasive electronics elevate an album of what could be some pleasant, if boring, pop tunes into a complex 47 minutes of constantly creative chaos. It’s a testament to the strength of the compositions that repeated listens do yield great rewards, revealing the paradoxical melancholy and joy behind many tracks here, making “Varmints” such a deeply gratifying and addictive listen.

        Album centerpiece “The Vapours” most clearly synthesizes a host of disparate musical influences. Over seven minutes, it takes the same guitar riff – worthy of a searing post-punk track – and filters it, repeatedly, until it is unrecognizable. Though the track is short by classical standards, it is composed in a similarly sprawling way. Myriad effects pedals synthesize and then re-synthesize the guitar, subtly changing the song like a great dance track. And, as usual, the melody is intoxicating, especially in the last minute or so, when the intricacies of the orchestration are irresistibly catchy.

        The only exception to all of the above chaos is the short, almost excessively beautiful “Blackfriars,” which ends the album after nearly an hour of exhilaration. There are no tricks up Meredith’s sleeve for this one, just an achingly sad violin phrase repeated for two minutes, employing the same trick as “Nautilus” – the melody is played more intensely each time. As the strings amplify, the song becomes a hypnotic, affecting dirge that seems like it could last forever, and listeners might find themselves hoping that it does.

“Varmints” is available on Spotify and Apple Music. It is also available on CD and vinyl through Moshi Moshi Records.