This thesis examines the intersection of neuroscience and musical theatre by analyzing how A Life Worth Living—an original musical centered on adolescent mental health—both represents and modulates the Default Mode Network (DMN), a brain system associated with self-referential thought, memory, and identity (Raichle et al., 2001). Drawing on current research in cognitive neuroscience, the thesis outlines the DMN’s role in depression, suicidality, and cognitive rigidity, then explores how these processes are externalized and represented on stage through character arcs, design elements, and musical structure. Chapter 1 traces the creative development of A Life Worth Living, from its initial inspiration to its full production and reception. Chapter 2 presents a neuroscience-based literature review on the DMN, synthesizing findings from clinical research to explain its role in psychiatric disorders and therapeutic intervention. Chapter 3 uses the musical as a case study to analyze how the DMN is portrayed onstage through character psychology, sound, design, and narrative structure, while Chapter 4 expands the discussion to consider how theater itself can modulate DMN activity. Through processes like narrative therapy, emotional rehearsal, and audience empathy, theatrical storytelling is shown to activate and potentially reshape DMN-related cognitive processes. Ultimately, this thesis proposes that theater can do more than represent the mind—it can participate in changing it. By combining scientific insight with personal narrative and artistic practice, this project suggests that interdisciplinary storytelling holds unique promise for mental health education, intervention, and healing.