A biographical film is in the works starring Colin Firth as Dr. Alex Comfort, the eccentric sex therapist and author of the groundbreaking erotic manual "The Joy of Sex." The film, which has begun principal photography, will chronicle the life of the man who became synonymous with accessible sexual education.

Firth will be joined by Julianne Moore, who is set to play Ruth Harris, Comfort's wife, whose marriage reportedly suffered following the manual's publication in 1972. The film's title has not yet been announced.

"The Joy of Sex," which has sold over 12 million copies worldwide and been translated into 30 languages, emerged from a more prudish era. Its frankness and explicit illustrations were considered revolutionary, particularly in contrast to the obscenity trial faced by the satirical magazine Oz for a sexualized parody of Rupert Bear shortly before "Joy's" release.

Nicholas Comfort, the author's only son, shared his perspective on his father's legacy in an interview conducted in 2022. He described his father as a scientist from north London who authored what is now considered a modern sex manual. Nicholas, a grandfather in his mid-70s, maintains a more reserved demeanor, dedicating his time to heritage steam railways and cricket, and serving as an elder in his local church.

Nicholas admitted to feeling "embarrassed" when his father's book was first published, particularly after his father made a public statement in 1963 urging teenage boys to carry condoms. "I wasn't embarrassed until people started teasing me about it," he said. Despite his father's public pronouncements on sexuality, Nicholas noted that Alex Comfort did not discuss sex openly with him, a common reticence among fathers.

Alex Comfort's personal life was as unconventional as his writing. While married to Nicholas's mother, Ruth, he had an affair with Ruth's best friend, Jane Henderson, whom he later married. The couple emigrated to the United States and became involved with the Sandstone Retreat, an open-sexuality resort. Nicholas recalled his father feeling conflicted about the situation, with Jane being the "needy" one and his mother being better able to cope independently.

Despite his father's progressive views on sexuality, Nicholas believes Alex Comfort would have been concerned by the ubiquity of internet pornography and the casual nature of modern hook-up culture. "He was a great believer that sex had its place as part of a caring relationship; not as something purely mechanical," Nicholas stated, adding that his father felt people's feelings should not be exploited.

The illustrations in "The Joy of Sex" were created by a real-life couple, Charles and Edeltraud Raymond, who volunteered for the project. Nicholas noted the genuine affection and tenderness captured in these images, which he believes cannot be replicated in contemporary pornography.

Alex Comfort, who died in 2000 at the age of 80, was also a proponent of free speech. Nicholas suggested his father would have been exasperated by the current stifling of academic debate on transgender issues, as he passionately believed in open discussion, even when opinions differed.

"The Joy of Sex" remains a significant work, with its core message emphasizing that intimacy and eroticism are most profound when accompanied by love. Nicholas Comfort's book, "Copy! A Life In Print, Parliament And Far Flung Places," is available on Amazon.