This interrupted case study is designed to highlight the importance of “failure” as part of the scientific process. Hypotheses that are disproven or experiments that yield unexpected results may feel discouraging, but they often provide critical information that drives future discoveries. The case narrative presents a fictitious scenario involving the mysterious decline of a native fish population. Students are asked to analyze the scenario using only the information provided, formulate a hypothesis to explain the environmental concern, and design an experiment to test it. New information is then revealed that requires students to discard their initial hypothesis and experimental design, reassess the scenario, and propose a revised approach. The case concludes with the presentation of simple graphs for students to interpret, allowing them to evaluate evidence and test the strength of their conclusions. Originally developed for a first-year introductory biology course at the undergraduate university level, the case is designed to develop skills of hypothesis writing and experimental methodology creation, while also addressing themes related to conservation biology, invasive species, and population dynamics, all of which are aligned with first-year biology curricular topics.