“AAAAAAH IT’S K-POP DAY” he wails…

[Video]
[6.90]

Madeleine Lee: “Back” reunites Infinite with Rphabet, the beatmakers behind “Destiny.” That song took elements of Infinite’s strings-and-sadness combo and turned them into speaker-grinding EDM; this song feels like the opposite, as if Rphabet listened to the mostly Sweetune-produced Paradise album and then tried to write a song like that, combining synthpop (“Be Mine”) with orchestral sweeps (“Tic Toc”). The production is as wall-to-wall as “Destiny,” but instead of just noise, there are delicate layers of instruments (classical guitar, strings, piano) over a crackling undercurrent, each contributing a few notes at a time. The quality of the vocals is weaker than on “Destiny,” but I’d blame that on everyone singing too high (which is, again, classic Infinite, but not one of the better qualities of their music). But what’s most important is the quality of the songwriting. Infinite’s never been much of a genre group — “retro” was always an approach to pop, not a replacement for it, and their best songs are the ones with the strongest bones. The slow part at the beginning of “Back” goes on for a bit too long for my liking, but the pause before the beat drop is just right, and the perfectly syncopated chorus is untouchable.
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Scott Mildenhall: The first Justice album was so good. Oh well. Infinite are well and truly keeping the dream alive, though this could be compared to any number of often French acts of that ilk. The punchy way they would use strings is there, but what’s more they have the audacity to have them unfurl into an “I Will Survive”-esque elegant disco glide, and it makes complete sense. Angular and smooth in one: quietly basking in anguish one minute, having a massive panic in a flashing room about it the next.
[8]

Alfred Soto: It sports an accordion interlude or something that reminds me of a bit from an early eighties Lime song, but the vocals and hoo-hah-hoo-hah synthetics don’t catch fire. 
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Edward Okulicz: Long after you’ve become sick of “I Will Survive” itself, you learn not to burden its children with that boredom. “Back” is an obvious, more chaotic mutation, but it gets all the benefit of its progenitor’s musical memes with little of the exhaustion of familiarity.
[7]

David Sheffieck: I wish a little more time was spent with the ballad sections, giving the hooks a harder punch when they dropped — instead, the song comes off almost off-puttingly frenetic. But I can’t deny that I love the way the chorus transitions from synth keys to strings and back, which is fun enough to overcome most objections.
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Micha Cavaseno: I haven’t heard a ballad so utterly self-deprecating in existence, especially one that relies on EDM production to give it an extra bit of muscle. As an utter babby when it comes to K-Pop, of course the first thing the piano reminded me of is the side-splittingly melodramatic “Haru Haru” of Big-Bang, a record that amplifies everything suspect about the group (G.D’s absurd “SAY GOOD-BUUUUUYYYYYY” will one day lead to me driving off a cliff, I assure you) and blasts it at you. I don’t know if Infinite are striving for that, but both the aforementioned song and “Back” parallel into similar territories of EDM-Ballad ‘Roided Out into the infinite bliss of divine soap opera cheese. Maybe I’m cynical, but the rising bubble effect (I wish I knew what that instrument was legitimately called), the purposeful sad-boy trance-transporter theremin-melody, orchestral stabs, careful stabs of fake sax that avoid the candy piping sax EFX that’s spread like wildfire, weeping descending strings that sound like steel pans. WEEPING DESCENDING STRINGS THAT SOUND LIKE STEEL PANS. For me, the deliberate caution of the placement, the need to hit all bases and the vocalists being so perfectly slotted avoids the domain of “absolute sap” that’d trap this record in my mind like amber fossilization.
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Iain Mew: “Back” is a rare song where a structural gimmick serves as its highlight even though the song can easily be imagined without it. Its sturdy pieces could be re-ordered as feathery ballad verses alternating with a disco blowout chorus, and it would still work. It just wouldn’t have quite the same roller-coaster thrill as using all the quiet bits for a long ascent ahead of one huge shiny drop.
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Will Adams: Just when it seems that there’s no coming back from the histrionics and the harmonic sequence, “Back” explodes into a shredded disco banger. It’s a brilliant switch that still excites after the fourth or fifth listen.
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Brad Shoup: It’s a waste to wonder what either section might’ve been, I guess: that windup synth only exists to set up the body of the song, although it’s fun to imagine a monotonous Greek chorus beigeing up a fine, arch romantic ballad. The main section is an odd fit, with that soap-opera piano subletting to squelchy claps and disco kick. Oh, and the guys are great: super intent and nearly camp-free, in deference to the racket going on around them.
[8]

Jessica Doyle: I still don’t love it. If I hadn’t already spent the last year and a half obsessed with Infinite I’m not even sure I’d like it. Everybody’s singing too damn high, for one thing. Everybody’s singing too damn high and somehow Sungjong’s falsetto still gets underused. The slowdown at 2:53 is one too many after that intro. The switches between members are often jarring — something handled more deftly in “Shower.” All that having been said, two things. One, Infinite’s lyricists specialize in the theme of I Will Get You Back Despite All Your Open Protests to the Contrary, Girl, but this is a step forward in acknowledging the existential fear behind such possessiveness. Two, even as I’m not playing “Back” over and over and over over over the way I have “Shower” or “The Chaser” or “Paradise” or “Shot” or “Hysterie“, I’ll admit that this new song somehow has enough force to consign their entire previous discography to a distant era.
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