In Twin Peaks: Fire Walk With Me, sound reinforces physical and mental transformations and changes in characters’ states of mind, especially Laura Palmer’s, which magnify how the film disrupts narrative certainty. Because it contains prequel and sequel elements, the film disturbs notions of time and conceptions of character. This chapter contends that, through different sound design, the film reinforces this disruption while reutilizing musical motifs from the show and creating a darker vibe. Generally, it utilizes understated, jazzier adult music that differs from the show’s synth-heavy soundtrack, which is especially evident when it deals with depictions of violence and sexuality. This vibe heightens tension as it unveils secrets of Laura Palmer’s life and her coming-of-age story alongside sound that indicates change and disruption. This chapter argues that mental transformation is key to the characters’ understanding of what is happening, and examines how music and sound reinforce and disrupt viewers’ perceptions of that understanding. Indeed, musical change represents Laura’s different personalities, from innocent to worldly, as sound reinforces her journey. The film’s sound design is critical in determining tonal shifts and creating unease, but also in providing viewer understanding for the shifting natures of characters’ moods and self-awareness.