One night a week, an actress or an actor will go up the stage, face the audience and immediately open a sealed envelope containing a paper with the text that will act at that moment, as well as the precise instructions to do so. At his side, there will be few elements of scenery to use as props. There is no director and there is no previous rehearsal, but it is not an improvisation. It is a theatrical experiment that challenges the actor and confronts the audience.