"I am a forest fire," Mitski Miyawaki sings on "A Burning Hill," the last song on her new album, Puberty 2. "I am the fire and I am the forest and I am the witness watching it." I can't imagine a better way to describe what Mitski does. Her great subjects are all interior: Sadness, fear, depression, the ever-elusive nature of happiness and inner peace. The way she sings it, she is at once the destroyer and the one being destroyed. And she's also the distant figure watching it, describing what she sees. You won't find many primal howls of pain on a Mitski album. Instead, she's found playful, faraway, sometimes even funny ways to sing about the sorts of feelings that can just gut you. She's a tough and meticulous writer, but her lyrics are only a part of the story. There's also her voice, an icy deadpan that, at times, takes on the same precise phrasing you'd expect to find in a jazz singer. And there's also the music, made entirely by Mitski and her producer Patrick Hyland. It's a quiet, personal, oblique take on indie rock with a beauty and an aesthetic sensibility that's entirely its own. Puberty 2 is one of those exceedingly rare moments where all three come together to make something bracing and exhilarating and new. It's an album with a quiet, profound force to it, a huge leap forward from an already promising artist.