The story follows their flight from the city after discovering they're on the police wanted list. They seek refuge at the waterside where Káyòdé's uncle Papa Emeka lends them a boat. As specified in your prompt, the boat engine makes "gbagba-gbagba" sounds as they navigate through the creek system into the mangroves.

Aṣàkẹ́ records the natural sounds of waves slapping against the wooden boat - "plap-splash-plap" - while Rírì prepares to play their sorrow mixtape. When she presses play, something magical happens: the music blends with the natural water sounds, and the lagoon itself begins to respond.

The chapter describes how the water starts glowing with phosphorescence where the music touches it, creating "tears of light" as the sorrow-anthem literally leaks into the lagoon. Fish gather around the glowing water, and the waves begin moving in rhythm with their bass line, showing nature accepting and transforming their musical resistance.

This experience teaches them that instead of fighting against the system, they might work with natural forces to create music that no government can control - sound that becomes part of the environment itself. The chapter ends with the realization that they've discovered a new form of resistance: collaboration between human emotion and the natural world.