As an artist and writer, Günter Grass has an encompassing interest in the transgression of boundaries; his work is full of intermedial connections. One of these intermedial characteristics is the recurrent use of musical structures, which has for a long time gone unnoticed. In this article I demonstrate how structural parallels to music – the use of transmedial categories of repetition, contrast, and simultaneity, in addition to a web of intermedial references to individual pieces of music – are used in order to undermine the linearity and causality of narration. To Grass, music and its structures are suitable means of achieving Vergegenkunft (paspresenture), a concept which he understands as a fourth tense in which past, present, and future can meet. The linear temporality of narration is thereby replaced by a temporal spatiality, a Zeitraum, that arises out of the simultaneity of different temporal narrative threads. I will give examples from the highly debated reunification novel Ein weites Feld (1995). In this novel, musical references to counterpoint and polyphony contribute to the ambivalence and multidimensionality of the novel.