A song by Charles Aznavour plays, in a karaoke version, and a dozen passers-by stop at a corner of Gaudí Avenue, in Barcelona, to observe a scene of strange magnetism. Joan Quintanilla, 82 years old, lanky and with a soft voice, performs the song with a perfect balance between emotion and serenity, with measured gestures and reciting each verse in impeccable French and with the classic elegance of singers from other eras. A few steps away, absorbed and with a lost gaze, Conxi Ventura, 75 years old, dances alone to the rhythm of the music. When the song ends – her favorite, she says, from a repertoire she knows by heart – Conxi is the first to applaud. “I am her number one fan,” she proclaims.