Senior Night explores the impact of mental health issues on family dynamics, particularly focusing on the experiences of siblings. It tells the story of Sarah, a star athlete and student, and her brother Dylan, who struggles with crippling depression. The script illustrates how Dylan's condition affects the whole family, especially Sarah, who often feels overshadowed and neglected due to the family's focus on Dylan. The narrative delves into the emotional turmoil and conflicts that arise within the family, highlighting the challenges and complexities of dealing with mental health issues and their ripple effects on family members.