In this article, we present the interactive opera project on CD-ROM Virtualis. This project includes a scientific dimension as well as artistic. It gave us the opportunity to design a model of the opera performance using formalisms from organization sciences. Moreover, our investigation on interactions between a user and opera contents led us to use models of relationships between entities based on physical forces, where the user is in a way absent. We detail some aspects of a reading but also writing environment on artistic complex contents between text, music and graphics.