Although born into a family of filmmakers, Ulysse took to music at a very young age. A trained violinist, he turned to electronic music in his teens. He began his career as a composer in 2008 with the short film L’enfant perdue by Joséphine Mackerras. In 2011, his parents, Nicolas Klotz and Elisabeth Perceval, entrusted him with the original score for Low Life. In 2013, he collaborated with Hélier Cisterne on the film Vandal. Ulysse and his sister, Héléna Klotz, composed the music for four films together: L’Âge atomique, Val d’Or, Bethlehem, and most recently, the short film Les sirènes de Chesnay.

In 2016, Ulysse showcased his talent in the film Jeunesse, directed by Julien Samani, moving seamlessly from powerful electronic themes to classical textures with the use of the viola da gamba. He has composed numerous original scores for Gabriel Abrantes, most notably for 'Diamantino', which won the Grand Prize at Critics' Week during the 2018 Cannes Film Festival.