Registered nurses are fundamental to the provision of high-quality care for older people with complex care needs living in residential aged care, where medical leadership is limited. Student nurses consistently prefer acute care-focused careers, which have implications for the aged care workforce. A mixed-methods study explored the impact of the first-year clinical placement in residential aged care on student nurses' career aspirations. First-year students from three Australian nursing schools were invited to participate in pre- and post-clinical placement interviews. 233 student nurses registered their interest. Thirty students at one nursing school participated in focus groups. Of the remaining 203 students, 108 (53%) completed a pre-clinical interview, and 102 (94%) completed a post-placement interview. A comparison of pre- and post-clinical placement interview data was conducted using reflexive thematic analysis. All students reported emotional responses associated with their first clinical placement in residential aged care. Before their placement, students were motivated, empathetic, and eager to learn, yet consistently described uncertainty, fear of harm, and anxiety about workplace relationships. Post-placement students’ emotional responses varied in intensity but were universal; prompted by moral distress, unpredictability, aggression, and ethical ambiguity. While student nurses enjoyed their clinical placement, especially the interpersonal relationships developed with older people, their career aspirations did not change. Curricula reform and sector engagement that improve students’ clinical placement experiences are required to build the next generation of nurses in the aged care workforce.