This chapter analyses the ways in which (un)sustainability is represented in the Netflix children’s film The Sea Beast (2022) from the perspectives of visual culture and environmental history. First, the film addresses the unsustainable use of sea resources, such as hunting and poaching. However, instead of portraying actual marine species, the film shows enormous fantastic monsters. The authors argue that monsters have been used to embody the non-human world and the concept of “nature” as something both beautiful and dangerous. Second, they demonstrate that the visual aesthetics of The Sea Beast are a recycling project themselves, as they are largely indebted to monsters depicted in Olaus Magnus’s famous Carta Marina created in the sixteenth century. The authors consolidate these two themes by problematising the film’s approach to (un)sustainability. Namely, they examine the ways human–non-human relations are portrayed, with non-humans depicted as needing to earn humans’ compassion. While monsters remain in the focus, the film does not encourage care for other non-human inhabitants and parts of the marine ecosystem. The authors further argue that while the film concludes by encouraging sustainable approaches towards marine environments, it does not provide a feasible answer on how to do so. By portraying a dreamlike universe inhabited by humans and monsters, The Sea Beast ultimately fails to address questions of sustainable approaches towards non-fictional species.