Morrison - a headstrong heroine blazing her way through a male-dominated industry - came to be a kind of mentor to Thorn. They shared the joy and the struggle of being women in a band, trying to outwit and face down a chauvinist music media.

In My Rock 'n' Roll Friend Thorn takes stock of thirty-seven years of friendship, teasing out the details of connection and affection between two women who seem to be either complete opposites or mirror images of each other. This important book asks what people see, who does the looking, and ultimately who writes women out of - and back into - history.

Tracey will be in conversation with the novelist, John Niven.

Photo credit and copyright: Edward Bishop