Rosalía sang flamenco Friday night at Joe’s Pub. She has height, and lankiness, and long expressive fingers, and a perpetually sensitive face, hot with emotion and soft with a kind of yearning. The air seems strung with filaments when she sings, quivering above, behind, and before her, and her tremulous lips part from time to time in an open-mouthed wail. Beside her sat the guitarist Raül Refree, who has a special gift for accompanying singers, whether to follow the voice or prod it, fill the gap or let it be.

She spoke little, except to express thanks and to say of Los Ángeles, her project with Refree, that it was on the theme of death. Flamenco is, of course, one of great genres of lament, a reservoir of loss and the strength to endure it, defiance over despair. It may be that all art is about developing an attitude toward death, but in flamenco and especially Los Ángeles, the impulse is particularly strong. The title evokes angels. Its lyrics are couched in the dense symbolism of folk poetry: the gravedigger’s shovel, the dagger and the coffin, the bodiless soul, the crucifixion, the desire to follow a loved one in death.

Yet for all that, the room was vivid with life. It is an irony that one so young and vibrant (she is 24 or 25) sings so beautifully on such a theme. Or perhaps not. Death can be premature, connected to love, of a heroic person or a beloved elder. And the point of Los Ángeles is neither to grieve nor wallow; it is to live through feeling, to lift up by means of emotion, transfigure through sound.

This is the third time I have seen Refree in a singer-guitarist duo (the previous two, at Joe’s Pub and (le) poisson rouge, were with the great Sílvia Pérez Cruz). He is assertive on his instrument, happy to bang on it or pluck it delicately as a lute. At one point he pulled the mike close to the instrument to capture the vibrations of the strings long after he’d ceased to strum them. Yet his connection to the singer is intuitive and unbroken, almost mystical, in perfect sympathy with the voice.

Los Ángeles is reportedly controversial among purists in Spain, presumably on account of Refree’s innovations. There is a touch of pop in Rosalía’s public persona, although I saw nothing on Friday but a committed artist honoring a tradition. Controversy or no, the house was packed and on its feet more than once. Something about the concert seemed to move Refree intensely. He appeared to bat away tears. Perhaps we witnessed an epiphany of which only they were aware. But what we saw was transformation enough: flamenco living and growing, rooted in history and bent to the sun.

Rosalía and Raül Refree were part of Flamenco Festival New York 2018. For more on Rosalía click here. Los Ángeles can be purchased here and heard here. Go to Joe’s Pub for events at that venue.