The opening line of "Boxer" is a perfect introduction to Stray Kids: Translated, it goes, "Hello, I’m a young man who can fly anywhere." It's a confident declaration, at once cheeky and polite, and it speaks to the Korean boy group's signature tenacity. It's charismatically delivered by main dancer Lee Know, the intensity building with every word. "Everyone, attention!" he spits before the song erupts into a flurry of chaotic synths and brazen emotions. It's loud and relentless, representative of the bold sound Stray Kids have been carefully honing since their pre-debut days in 2017 — and of the group itself: eight young individuals navigating the labyrinth of adulthood. (A ninth member, Woojin, left the group in late October 2019 for personal reasons.)

That tempestuous coming-of-age journey is seeped into their ambitious March EP, Clé 1: MIROH. Inspired by the word miro, or "maze" in Korean, MIROH kicked off a confident new chapter for Stray Kids, beginning to answer the introspective questions posed by their 2018 I Am... series of EPs, which focused heavily on the theme of identity. Who am I? Who am I trying to be? And importantly, who do I want to be? With MIROH — the first in the Clé trilogy, which also includes June's Yellow Wood and December's Levanter — these important questions persist, but Stray Kids strengthen their resolve as they charge away from the systems that seek to control them and into the thorny, often scary unknown.

That maturity isn't just reflected in the lyrics and production, so thoughtfully crafted by the members themselves, but on Clé 1: MIROH as a whole. Released a year after their debut, the group's fourth EP is their strongest and most cohesive body of work. Etched into these seven songs is not just a story, or a concept, but a collective journey from self-doubt to resilience. The album's intro track, "Entrance," invites you into the chaotic world of MIROH — rich in texture, pulsating beats, and ad-libs from other songs on the album — with assurance.

At first listen, "Miroh" sounds like an odd choice for a lead single. It's a cacophony of sounds, rhythms, chants, and animal noises that doesn't seem to follow any familiar song structure. There's no real melody, just powerful rap verses over a repetitive bass line. But the hook is massive; it's meant to be screamed at the top of your lungs, like the K-pop imagining of a My Chemical Romance headbanger — that is, if Gerard Way had been less a fan of The Misfits and more into EDM. It isn't a song so much as a heightened experience.

In the greater K-pop landscape, wherein melodic sound is mainstream, "Miroh" is fearlessly defiant. It's unabashedly noisy, and its message is resilient. As Stray Kids rush into the maze before them, they do so with impenetrable confidence. "But there’s no time to rest," Hyunjin smoothly raps on the second verse. "I’m alright, I’m holding on and I keep on going / I just need to look ahead and run."

Running is kind of their thing. Stray Kids have been releasing music at a tireless pace since "Hellevator" premiered in October 2017. The angsty pre-debut song established the JYP Entertainment-repped boy group's grungy style and affinity for explosive EDM drops. They made their official debut in March 2018 with "District 9," a genre-agnostic track about disaffected youth with in-your-face energy and staggering rhythmic intensity. Since then, they've released six EPs, particularly impressive for a group who write and produce all of their music.

Members Bang Chan, Changbin, and Han — otherwise known as the production trio 3RACHA — are responsible for a heavy majority of the group's discography. They're credited lyricists and composers on every Stray Kids track to date and have been making music together since their teenage trainee days, uploading self-produced mixtapes to SoundCloud and YouTube. The other members also participate in the songwriting process; they all contribute lyrics to the mixtape songs that are part of each physical release — like MIROH's "Mixtape #4," a rearranged version of 3RACHA's "Broken Compass" about the importance of trusting yourself and following your own path, no matter how scary the road ahead looks.

Stray Kids challenge these fears throughout MIROH. "Victory Song" is an anthemic rallying cry to move forward with confidence and bulletproof ego. "Who else is like me, there’s no one," Han raps. But that bravado starts to crack on "Maze of Memories," a dizzying track that stimulates the feeling of wandering in hopeless pursuit of an end that's nowhere in sight. "Now I run for an answer that I cannot see," Han laments. There's an uneasy cadence to the track as it switches between two tempos; it's disorienting and visceral, like the experience of growing up. "Chronosaurus" is similarly introspective. The song, inspired by leader Bang Chan's own fascination with time, personifies the phenomenon as a monster they must outrun. "Day and night, every day," Seungmin sings. "I am afraid / I think I'll get caught."

Time is a continuous theme for Stray Kids. On the EP's standout track "19," written and produced by Han, they yearn to stop time. It's a confusing paradox, the desire to grow up but fearing the real meaning of being an adult. But the ways in which Stray Kids empathize with this conflict is precisely what makes them the voices of their generation. "Twenty years old that I wanted to become so badly," Han raps. "Did everybody go through this same experience or am I the only one that’s anxious?"

And while main rappers Changbin and Han get plenty of room to flex on the album — Changbin's aggressive bite is a perfect match for Han's more melodic flow — MIROH smartly showcases rappers Hyunjin and Felix as a testament to their growth. Hyunjin's versatility is his strength. On "Maze of Memories," he switches up his flow effortlessly, a potent mix that leaves you breathless. Elsewhere, Felix delivers one of the album's smoothest verses on "Victory Song" with a newfound sense of confidence. Vocalists Seungmin and I.N also shine in unexpected ways; Seungmin's English rap on "Maze of Memories" is a genuine highlight, while youngest member I.N. soars on "Chronosaurus."

Throughout the Clé series, the members of Stray Kids are running toward something that is never clearly defined. That's the point: the realization that the destination doesn't matter nearly as much as the journey. But the journey isn't an easy one. Sometimes the voices inside their heads get too loud, too consuming, and feel insurmountable. But that's what makes MIROH a seminal work from the young group — just because you can't see your way out of the maze doesn't mean you should stop trying.

Find all of MTV News's 2019 Albums of the Year right here.