A new poetry collection from Britain's foremost truth-teller, in Divisible by Itself and One Kae Tempest masterfully steers a path between their more public-facing performance and dramatic work and the contemplative voice that came to the fore in Running Upon the Wires. Questions of integrity – hence the prime number of the title – are addressed in direct, affecting terms: how can we be true to ourselves while under constant pressure to conform? Throughout the poems, ideas of form – of the body, gender, and in nature – resurface and resolve. Stories of transformation hold a central place in Tempest’s work, their best to date; here, the poet considers the changes that are sometimes required to be oneself.