Nami joins her Straw Hat crewmates attending Uta's debut concert on Elegia. During the performance, Uta uses her Sing-Sing Fruit power to trap the audience, including Nami and most of the Straw Hats, within a dream world she controls completely through song.

Initially captured within its confines, Nami later escapes captivity alongside her crew. She participates in the effort to counter Uta's powers and free the trapped individuals. When Nico Robin discovers research in Elegia's library revealing the demon Tot Musica can exist in both the dream world and reality, and that defeating it simultaneously in both realms would free everyone, Nami supports this plan. She assists in the coordinated effort against the demon.

In the final confrontation, Nami contributes to the battle against Tot Musica. Usopp establishes a mental link with his father Yasopp using Observation Haki, enabling the Straw Hats and Red Hair Pirates to synchronize their attacks across both worlds. Nami is part of this pivotal effort, allowing Luffy and Shanks to deliver the finishing blows. Following Uta's sacrifice to sing a song returning everyone to reality, Nami departs Elegia with the Straw Hat Pirates aboard the Thousand Sunny and resumes her duties as the crew's navigator.