This is Maugham in 1907, on how he came to write Lady Frederick, the first of more than thirty plays to be (as almost all of them were) a huge success: 

I reflected on the qualities managers demanded in a play: evidently a comedy, for the public wished to laugh; with as much drama as it would carry, for the public liked a thrill; with a little sentiment, for the public liked to feel good; and a happy ending. Having made up my mind upon this the rest was easy.

And there, early in an astounding career which made him more famous than any writer could hope to be today, you have much of what he was as a writer. 

But not all. It leaves out his consuming interest in people – the detached but piercing interest of a naturalist studying a species – and his creative energy. He was not a great writer, but he was a phenomenon: a living machine compelled by its nature to observe, and then to turn what he had observed into stories (or plays, or novels) which people enjoyed so much that they sold by the million all over the world. He was also determined. Lady Frederick had been rejected seventeen times because the leading lady had to appear at one point stripped of make-up, which actresses refused to do. Maugham persisted in pushing the play, knowing that the scene in question would work – and it did. He was a formidable operator.

He was also, to start with, terribly unhappy. His adored mother died when he was eight and he was consigned to the care of elderly relations, not cruel but unused to children and profoundly boring. He developed a stammer, so when they sent him to school he was bullied and teased. He coped by building a thick shell of reserve and control over exceptionally stormy emotions – and was well aware of his own tactics.

Once out in the world he began to thrive, educating himself rapidly, flexing his writing muscles, and making friends. In old age he looked like a fierce crocodile and sometimes behaved like one, but earlier, though he soon gained a reputation for cynicism, he was generous in admiration (as he always was with the great amount of money he made), and unfailingly courteous. He finally came to know ‘everyone’, hobnobbing with Charlie Chaplin, taking tea with the Queen, familiar with all his fellow writers and pretty well every other famous person of the day, but also making enduring friends simply because of mutual esteem and affection. One of his closest friends, the painter Gerald Kelly, said after his death, ‘Willie was a duck – an absolute duck’, words which would have surprised those who knew him only superficially – particularly as Kelly was not gay.

Maugham was bisexual, and – probably misled by having a happy eight-year love affair with a woman called Sue Jones, who was easy-going enough to allow him leeway – he made a serious miscalculation, concluding that he was three-quarters heterosexual and one-quarter homo, when it was really the other way round. So when he let himself be manoeuvred into marriage by the ruthless and (one comes to think) appallingly silly Syrie Wellcome, he plunged into disaster. He had just met Gerald Haxton at the time.

Haxton wanted ‘fun and games – someone to look after me and give me clothes and parties’. He found someone who gave him his whole heart. For many years the imbalance of their feelings hardly mattered because Haxton loved travel as much as Maugham did and enjoyed being an invaluable companion on the many journeys they made together, but no doubt it contributed to the relationship’s sad end, and Haxton drank himself to death, leaving Maugham shattered.

All this is chronicled brilliantly by Selina Hastings, whose research, empathy and style cannot be faulted. With the same skills she pilots us through the rest of his life: his eventual escape from Syrie, his creation of an idyllic home in the South of France with the devoted Alan Searle, his wartime work for the secret services – a fascinating and little-known part of his life. His end was even sadder than his childhood, bedevilled by dementia and by the fact that Searle’s devotion did not prevent him from being a troublemaker, but it was only a short period of an otherwise triumphant life.

Hastings was faced by a problem because of the length of Maugham’s life, and the fact that a writer cannot switch from the meticulous detail so valuable in the building of a portrait to an impressionistic style that whisks you through time: such a switch does not work. On the other hand, more and more meticulous detail comes to seem like too much of a good thing. Towards its end this book does begin to stagger under its own weight. It remains, however, an impressively perceptive and often moving account of an extraordinarily interesting man, and an astonishing reminder of the dizzy heights to which literary success could once carry a writer.