The film opens with someone on the radio asking what a hippo sounds like. Wild hippos can be highly vocal and noisy; curiously, those kept in zoos are usually much quieter. This is demonstrated in the subsequent scenes showing the animal in the wild, before it is captured, vocally interacting with other hippos as it begins to narrate and declares "I never heard the sound that comes out of my mouth". Yet the noises heard during this exchange are not hippo sounds, leaving the audience uncertain about the animal's actual voice.
The narrator says they were eighteen when their brother, Pablito, killed their father and began a "reign of terror". By 2023, Colombia was home to about 120 hippos. In contrast to African hippos, the Colombian animals are far more aggressive; research indicates behavioural changes started to appear between the second and third generations in the area, with rising tensions between the hippos, the local fauna and the communities along the Magdalene River, the nearest body of water available for migration from Hacienda Nápoles.
Although hippos are indigenous to Africa, the Narrator's voice never uses any of the continent's native languages. Instead it is heard speaking German and Afrikaans — both tongues brought to Africa through the violent processes of colonisation. The same pattern appears when the Narrator operates in Colombian territory, speaking Spanish, a language imposed by colonial violence, while none of the indigenous languages that would resound along the Magdalena River and across native lands in Colombia are heard.
The film combines drone cinematography with concealed wildlife camera footage to portray its central characters — the hippos.
Drone footage over the Magdalene River lays bare the danger posed by hippos: it is impossible to ascertain their location unless they surface on camera, or the picture contrast is increased to reveal their silhouettes in the water.
