Nancy Friday’s groundbreaking anthology My Secret Garden: Women’s Sexual Fantasies was first published in the US in 1973, though Gillian Anderson only read it for the first time when she took on the role of sex therapist Dr Jean Milburn in Sex Education. “Their unfiltered and painful honesty shook me,” she says of Friday’s letters and interviews in the introduction to Want, a new collection billed as the 21st-century update. Considering the issues raised by Friday’s book – what women want, and how that relates to the gender roles imposed on us – led Anderson to question how much might have changed in the intervening half-century, and to issue an appeal for answers.

Where Friday put an anonymous advertisement in a newspaper, the Dear Gillian project’s online portal had the potential to reach a global audience, and the responses amounted to nearly 1,000 pages. Anderson’s role has been to curate these into a more manageable selection, organised thematically: “Kink”, “Strangers” and “Power and Submission” are among the more obvious headings. Sceptical readers might be asking themselves what qualifies Anderson to edit a volume on this subject, beyond having played a sex therapist, but she is quick to offer a disclaimer. “I am not an expert and have no professional qualifications in this area,” she writes. “I am an actor by trade, and will therefore not be analysing these letters, or offering explanations on womanhood or sex in general.” What she does provide is a brief overview at the beginning of each section, occasionally including a personal anecdote that stops short of revealing anything truly intimate. But she has also hidden her own anonymous fantasy somewhere in the pages as a tease to the reader. ‘Would it match people’s assumptions about me?” she wonders.

The determinedly curious could attempt to narrow it down, because each contribution identifies its author by their (self-defined) nationality, ethnicity, religion, salary bracket, sexual identity, relationship status and number of children. The editorial choice to include earning power as a marker rather than age strikes me as a baffling one; not knowing how much life experience a writer brought to her story felt like an omission, while income seemed to have little relevance.

The letters included here represent, as promised, a colourful range of scenarios, confirming that increased representation and openness about female desire across the media in recent decades, together with greater acceptance (in some cultures) of more unconventional sexual arrangements, have resulted for many women in a more confident articulation of what they want (hence the title, though I feel they missed a trick in not calling it The XXX Files). More surprising, perhaps, is how many taboos from Friday’s time persist, and how much some women – even in supposedly liberal cultures – still experience crushing shame around their sexual feelings.

Elegant prose is not the main point here, so there is little mileage in critiquing Want for its literary qualities. Some of the pieces are fluently written, others are laden with cliche, and a depressing number betray the influence – both in style and content – of Fifty Shades of Grey. Power dynamics play a significant part in many of the fantasies, and there’s a palpable nervousness on Anderson’s part – and on some of the contributors’ – around the fact that women often fantasise about encounters involving violence, coercion, captivity and other degradations that would be horrifying in reality. Anderson is careful to clarify that the significant factor here is agency, and that the point of fantasy is that we are always in control; even so, there are one or two contributions that may make some readers uncomfortable, particularly where the writer mentions their own history of childhood abuse.

Almost more engaging than the rich inventiveness of women’s imaginative couplings (or more) is the glimpse many writers offer of their emotional lives. Some contributions are shot through with painful longing (women in loveless marriages; widows dealing with grief; queer women afraid to come out), and several explicitly say that they have never been able to express these feelings until now. Others are funny and exuberant, a celebration of pleasure. Overall, Want is an intriguing cabinet of curiosities showcasing the sheer glorious variety of female desire; at a time when women’s freedom of expression and agency is under threat in so many places, any platform that allows us to speak up about an aspect of our lives that is still frequently veiled in shame is to be applauded.