Strictly speaking, love letters and diaries are not short stories – but they can reveal a great deal about a writer’s creativity and shine a light on their lives.

Such was the case when Charleston gave a warm welcome to artist Don Bachardy, Christopher Isherwood’s partner and soulmate for more than 30 years.

The relationship was unconventional to say the least – the celebrated author of Goodbye To Berlin first encountered the sprightly youth 30 years his junior on a Santa Monica beach.

In the slightly chillier surroundings of Charleston, a discussion between Bachardy and Katherine Bucknell, editor of The Animals: Love Letters Between Christopher Isherwood And Don Bachardy, was followed by a touching 2008 documentary. Both events looked back at the relationship “for which there was no blueprint and through which they had to find their own way”, as Bucknell explained in her opening words.

Isherwood died in 1986 in the Santa Monica house the couple shared all their years together. Bachardy, by that time an established portrait artist, recalled in the film how he feverishly kept painting and drawing his partner through his agonizing illness – and even after he had died.

Perhaps it was not surprising that a question from the audience about how the relationship developed brought him close to tears and struggling for words. “If you could have known him and spent an hour with him I would not have to answer that question. He had eyes that ate you up. He was the most extraordinary person – so reassuring – he meant everything he said to me. He is still a great support to me.”

Snappily dressed in jacket, tie and white trainers and with an infectious high-pitched laugh, Bachardy was also full of humour, poking fun at his youth when he recalled how he and his brother would trick their way into Hollywood movie premieres, rubbing shoulders with their screen idols.

Once engulfed within Isherwood’s social world, Bachardy found he was frequently befriending the rich and famous and had numerous celebrities willingly sit for him – how many people can count Igor Stravinsky among their former circle of chums?

Through Bachardy’s recollections, the love letters and the home movies the couple made of each other, the relationship came across as warm, genuine and fulfilling. Despite the expected ups and downs, it endured through Hollywood prejudice and duplicity. That has to go down as a blockbuster of an achievement.