Moondog, the Viking of Sixth Avenue, haunted the asphalt jungle of New York and minds of the time, transcending musical chapels: Arturo Toscanini, Charlie Parker, Leonard Bernstein, Janis Joplin, Allen Ginsberg, Philip Glass or even Terry Riley have met him this way. If this surreal character has left the surreal world of the living, his soul still lives in many musicians. It is on this terrain that moves “Perpetual Motion,” the creation-event conceived by Sylvain Rifflet with his fellow American saxophonist Jon Irabagon, who invites his brilliant Alphabet quartet, pianist Eve Risser, and even two Bobigny college choirs. The challenge: reinvest the music of Moondog, query the sprawling and spectacular city (the video has its place here), and take off to other imaginary areas.