Julius Caesar by Brutus, the McDonalds by the Campbells, Hitler by Himmler, Prince Harry by his family… history (and literature, think of Macbeth or Miss Brodie) is littered with famous betrayals. From politics to artistic feuds betrayal is often the basis of delicious stories.

One of the most famous is that of Truman Capote’s betrayal of his female friends in his final novel which ended his career and tipped him over the edge. It was one of the most famous falls from grace in the 20th century. The moral of his story (as true for his victims as it was for Capote himself) was that wealth does not buy happiness.

A supremely gifted writer from an early age, by the late 1950s Capote was a celebrity as much as a literary figure. His novella Breakfast at Tiffany’s was made into an iconic film and he had been desperate to make his next book the Great American Novel. His groundbreaking ‘non-fiction novel’ In Cold Blood, about two drifters who murder a hapless farming family published in 1965 has claims on being one of the top ten true crime books.

The story of the ignominious fall of the writer is told in a new book Capote’s Women by Laurence Leamer (soon to be adapted for TV with Tom Hollander, Naomi Watts and Chloe Sevigny). Tells of the author’s gal pals – Babe Paley, Slim Keith Gloria Guinness, Mariella Agnelli, Pamela Hayward, CZ Guest and Lee Radziwill – and how and why he betrayed them.

Capote prided himself on his photographic memory, his reputation was that of a great listener and loyal confidante (and a judicious gossip). His lady friends (he called them his Swans) were tall, elegant, rich and married to powerful and influential men. They could also be desperately unhappy. But Truman was there to offer support and patiently counselled them as they whined about their blighted lives and the men who constantly let them down.

What better for his next novel than a story to match Henry James, Edith Wharton, Proust and F Scott Fitzgerald and their tales exposing the wealthy elite for what they were – failings, foibles, felonies and all. Almost before a word was written 20th Century Fox were offering an enormous advance for the film rights (when everything went belly-up, he had to pay it back).

The book, the author hoped, would give his credibility and celeb status a new lease of life. The unfinished novel, Answered Prayers (‘more tears are shed over answered prayers than unanswered ones’ wrote St Teresa of Avila) told his Swans’ secrets only lightly disguised. “All literature is gossip,” Capote told Playboy magazine after the controversy erupted. ‘What in God’s green earth is Anna Karenina or War and Peace or Madame Bovary, if not gossip?’’

When a friend (reading the manuscript) questioned the advisability of his kiss-and-tell novel and suggested that the real-life subjects of his fiction might recognise themselves and not be best pleased Capote replied: “Nah! They’re too dumb.”

However, when an extract was published in the November 1975 issue of Esquire magazine there was a furious reaction. As one observer put it “he had unwittingly turned the gun on himself: exposing the secrets of Manhattan’s rich and powerful was nothing short of social suicide.”

William Paley (the head of CBS Television) and his wife Babe had been among Capote’s most ardent supporters. There were gifts, introductions to important people. Capote was regularly their travelling companion and he adored Babe. He once wrote in his diary ‘Mrs P had only one fault: she was perfect. Otherwise, she was perfect.’ But when the Paley’s read Esquire’s blood-on-the-sheets extract they immediately recognised themselves and knew that their social set would too. When Babe broke off contact with her friend (she never spoke to him again) Capote was devastated. His project was abandoned and the book remained unfinished.

So why did Truman Capote do it? There are many theories. One suggests that he never got over being abandoned by his mother who died tragically. Answered Prayers was the act of a bitter man who was losing his literary abilities. Perhaps he knew he would never write anything as good as In Cold Blood again and floundered. maybe he was afflicted by writer’s block.

There were certainly endless delays in furnishing his publisher with even parts of the manuscript. His mind was frazzled by booze. Was his act of self-sabotage just the arrogance of a genius writer? As Leamer says: ‘as much as Truman was drawn to the world of privilege he was repulsed by its arrogant sense of superiority and ignorance of life as most people lived it. Life had a way of intruding and teaching hard lessons. The tension between these two beliefs would create his immortal book’.

If there were casualties along the way, so be it.

When once asked why he betrayed his friends Truman Capote simply answered “What did they expect? I’m a writer.” ■

Twitter: @KenWilson

Info: Capote's Women: A True Story of Love, Betrayal, and a Swan Song for an Era by Laurence Leamer, Hodder & Stoughton, £25