Inside, she discovers an unfinished musical composition with strange notations. Meanwhile, sound engineer Julian finds a recording containing part of the same melody at Radio France archives. The melody produces powerful effects—triggering synesthesia in non-synesthetes and evoking different emotional responses in each listener. With guidance from Madame Charelle, a former student of Savard, they learn the melody is an auditory cipher designed to unlock ancestral memories encoded in human DNA.