Cartes sur table, the third and final volume of the Lou! Sonata trilogy, marks Lou's transition into adulthood. At 22, her life becomes more complex with the return of her father, the arrival of a half-sister named Jeanne, and a mysterious card game that reflects her inner questions and uncertainties. The story unfolds as Lou celebrates her 22nd birthday at the Mortebouse music festival, a setting that adds both emotional and artistic depth to the narrative. The album's release is accompanied by two new extensions of the Lou! universe: a soundtrack titled Lou! Sonata Vol.3 by Krystal Zealot, available on vinyl and CD, and a 64-card game called Le Mystérieux Jeu de cartes de Lou!. Julien Neel, the creator of the Lou! series, has remained deeply involved in expanding the world of Lou. He directed the 2014 film adaptation of Lou! Journal infime, one of the earlier works in the series. In 2018, the first season of Lou! concluded with the eighth volume, followed by an integral version the next year. In 2019, Neel launched Le Petit monde de Lou! with Glénat Jeunesse, a new collection of thematic albums aimed at younger audiences. The following year, Lou's journey continued in Lou! Sonata, which began as a graphic novel, further solidifying her transition into adulthood. To support the evolving Lou! universe, Julien Neel collaborates with the music group Krystal Zealot on a narrative and eclectic soundtrack. This partnership is part of a broader initiative, as Neel founded the association Musimagik to develop and implement such creative projects. In 2026, he also created the poster for the Partir en Livre festival, showcasing his ongoing commitment to both music and literature. The Lou! series has grown significantly over the years, with each new release adding layers to Lou's story. The final volume of the Sonata trilogy, Cartes sur table, not only concludes her journey but also opens the door to new creative formats, including music and games, that allow fans to engage with Lou's world in different ways. This expansion reflects the series' evolving nature and its ability to adapt to new artistic expressions.