Catherine
The daughter of a recently deceased, esteemed mathematician. She is gifted in her own right but fears she will inherit the same mental illness that plagued her father in his final days. Despite her mathematical brilliance, Catherine tends towards lethargy and spends much of her time idle and depressed. She has a sharp and biting wit that she does not hesitate to launch at those around her when they have upset her. Her intense defensiveness springs from a crippling fear of failure and decline. She is hyper-logical, and often denies herself the simple pleasures of self-care. For instance, when her sister Claire insists that she use a shampoo that will improve hair health, Catherine reminds Claire that "hair is dead."
Hal
A former, devoted student of Robert’s who wishes to search through his mentor’s work. Despite a budding romantic relationship with Catherine, he remains doubtful of Catherine’s mathematical genius throughout the play, which disappoints Catherine in major ways. Hal is lovable, nerdy, but a little sexist in his preconceptions and his perception of Catherine. He plays in a geeky band with other mathematicians.
Claire
Catherine's practical and unimaginative sister. Claire lives in New York City and has a successful career, having gotten away from her family and her youth. Her care for her sister and her desire to help Catherine is blunt and often intrusive. Rather than recognize that she and her sister want different things, she pathologizes their differences and makes decisions for Catherine even when Catherine is capable of making her own. Claire is the closest thing the play has to an antagonist, even though she is acting from a pure-hearted and well-intentioned place. She just wants to help her sister get better, even if her methods are aggressive and unwanted.
Robert
Robert is Catherine and Claire's father. A brilliant mathematician, he completely changed the field by his mid-twenties. In his later years, his mental health took a turn for the worse, as he became more and more prone to delusion. He is a tragic figure in the play, but he was also a brilliant force and a beloved father. Of all the people in Catherine's life, he is the one who believed in her the most.
