This portrait of the Ensemble Intercontemporain, in residence at the Cité de la Musique de Paris, looks back on 30 years of creative activity, through a playful access to the world of contemporary music. Archive images and filmed sequences give us the opportunity to see, hear and understand the formidable human adventure of this unique ensemble, engaged in the musical creation of our time. In a form of polyphonic architecture, the film introduces us to Pierre Boulez, founder of the Ensemble intercontemporain, and Suzanna Mälkki, current director of the Ensemble, but also to composers and conductors in educational sequences, on tour or working in a recording studio.