Background: Quantitative researchers have noted the impact of mentoring and support programming for students from underrepresented groups in engineering. Qualitative researchers have also noted the importance of student agency in persistence through marginalization. Nevertheless, challenges and questions remain in identifying practices which are effective in supporting underrepresented students. Purpose: The study applies scholarship from critical theory and narrative as a new resource for approaching and understanding the process of supporting marginalized student agency. Method: A longitudinal interview study with a female undergraduate engineering student, Emilia, developed into a way for her to process marginalizing educational experiences and to develop new narratives that expanded her agency. After an in-depth member check, Emilia became a co-author contributing a post hoc account of the impact of these discussions. Results: Our analysis indicates that naming one's own oppression and creating narratives that repurpose and resituate stereotypical stories of oppression was a liberatory act for Emilia. We trace three marginalizing themes of the participant's experience that are subverted and resisted through the student co-constructed narrative. Conclusions: The paper builds theory for diversity support, suggesting critical theorizing may present a new form of agency not yet represented in the literature. It also points to possible value for student participants from qualitative methodologies exploring student experiences. Finally, it suggests supporting critical theorizing as a potential new orientation for diversity practitioners.