Chloe Caldwell's period has often felt inconvenient or uncomfortable or even painful, but it's only once she's in her thirties, in a new relationship, that its effects on her mood start to dominate her life. After realising that her outbursts of anxiety and rage match her hormonal cycle, Chloe documents attitudes toward menstruation among her peers and family, reads Reddit threads about PMS, goes on and off antidepressants, attends a conference called Break the Cycle, and learns about premenstrual dysphoric disorder, PMDD, which helps her name what she's been going through. She also reflects on other underlying patterns in her life: her feelings about her queer identity and writing persona in the context of a heterosexual relationship; how her parents' divorce contributed to her issues with trust; and what it means to blend a family.