This composition is both a milestone and an interface in Silvestrov's work: it is the end of his 'avant-garde period' and the beginning of what he later calls 'metamusic'. The structure of the work is unique: The first movement, Sonata for Violin and Piano, can also be performed separately. The second movement, Sonata for Violoncello and Piano, is a kind of lyric intermezzo. It is not until the third movement, Trio, that the instruments really play together, bringing the drama to a 'metaphysical end'. The work is characterized by an exceptional variety of tone colours, playing techniques and tonal systems. Some visible activities of the musicians on the stage have nothing to do with superficial 'instrumental theatre' but hold a deep symbolic meaning.