For Ivan Moffat, like so many other Brits who made their way to Los Angeles after World War II, movies were less a calling than merely a ticket to living well. The writer, who died recently at the age of 83, had his greatest professional successes decades earlier, with “A Place in the Sun,” “Shane,” and “Giant.” By no means masterpieces, these works did capture a certain 1950s moral seriousness – and were enough of a calling card for Moffat to putter along in Hollywood for decades, supporting himself with odd projects.

Moffat’s final years found him living in relative poverty, helped along by a few friends willing to trade dinner for his studio-era lore. “The Ivan Moffat File: Life Among the Beautiful and Damned in London, Paris, New York, and Hollywood” (Pantheon, 352 pages, $26), a posthumous collection of Moffat’s autobiographical writings assembled by a Hollywood biographer and screenwriter, is like a bound version of this bon vivant’s banter. Moffat rubbed bespoke elbows with everyone from Ernest Hemingway to Dylan Thomas to Charlie Chaplin – who, according to Moffat, banned Christopher Isherwood after a raucous soiree at his home that left urine stains on his couch (though Moffat says Thomas – who seems never to have been without several cocktails in him – was the real culprit).

The seeds of Moffat’s social success were sown early. The grandson of famed actor Sir Herbert Beerbohm Tree (and nephew of satirist Max Beerbohm), Moffat was born to glamorous artistic parents whose acquaintances included Coco Chanel, Man Ray, Cecil Beaton, and the Bloomsbury crowd. His mother, Iris Tree, was a poet and actress (she would later appear in “La Dolce Vita,” for which Fellini tricked her into declaiming on camera a line that she found too close for comfort: “I drink to my lovers and to my whiskey”).

Yet the same parents who provided Moffat with peerless social entree also neglected him. “I felt a need to over perform and to pretend,” Moffat said of his social climbing. In London, he became a regular at the Gargoyle Club, whose guests – Noel Coward, Virginia Woolf, Osbert Sitwell, and the Mitford sisters – used the club as “a social and sexual gymnasium.” Moffat’s womanizing was also a likely product of his upbringing, if only because of the freedom provided by the lack of parental supervision.

Moffat’s first sexual experience was with his cousin Veronica, while he was still in short pants, and so began a lifelong pursuit of the fairer sex. Moffat’s sexual prowess was large (though his appeal remains opaque to a reader). Mr. Lambert conjectures that Moffat had “walkouts” – Moffat’s term for assignations – with more than 200 women, many wives of friends and colleagues, some movie stars. He bedded Merle Oberon, charmed Natalie Wood, and fondled Elizabeth Taylor – of whom he remarked, “I once began kissing her and she seemed to like it, but unfortunately there was no time for more, she’s always so busy.”

Moffat’s children and failed marriages register as little more than blips in “The Ivan Moffat File”; his energies lay elsewhere. The only woman – indeed, person – who seems to have held his interest was Caroline Blackwood, whom the 38-year-old Moffat romanced between her marriages to Lucian Freud and Robert Lowell. It was likely Blackwood’s emotional unavailability that intrigued Moffat, as it mirrored his own and offered him with a singular challenge – or perhaps just a narcissistic thrill.

“The Ivan Moffat File” is a curious book. The title has the glamorous ring of espionage or surveillance, but in fact just describes the scattershot materials between its covers. A lengthy introduction by Mr. Lambert precedes Moffat’s own unfinished memoir, “Absolute Heaven.” Memories of a lonely childhood and a punishing English boarding school education come together in a hybrid of Evelyn Waugh and Proust. The memoir is not without charm, but in its fragmentary and superficial state, seems half-baked.

More interesting, or at least more fun, are the sketches and interview transcripts Mr. Lambert has included to fill out the volume. It’s there you’ll find an insider’s glimpse into the casting of Shelley Winters, Montgomery Clift, and Ms. Taylor in “A Place in the Sun.” It’s also where Moffat tells of the strange and wonderful note Preston Sturges left in the toilet stalls in Paramount studios’ bathroom after he was fired from “Roman Holiday.” Sturges’s missive instructed on the proper use of sanitized toilet seat covers and was written in what Moffat describes as “Elizabethan English.” Moffat covered the note with cellophane and Scotch tape in an attempt to preserve the poetic against a Hollywood that had come to overvalue the vulgar.

“The Ivan Moffat File” is perhaps best read as a cautionary tale. Unlike Sturges, Moffat was only moderately talented. His emotional vacuities and his bloodlessness prevented him from leaving much of a mark – with moviegoers or even his own children. His life, at least in this volume, seems little more than a string of anecdotes.

Including this one: When a stripper Moffat had been dating disclosed to him her drug addiction, he took her to a psychoanalyst. The therapist, in turn, suggested Moffat himself would benefit from treatment – three times a week, at 50 pounds a session. “I would gladly pay you double that amount,” Moffat retorted, “for the pleasure of not seeing you three times a week.” Such resistance to self-examination accounts for Moffat’s popularity on the dinner-party circuit, but leaves the reader little to chew on.

Mr. Schmidt last wrote for these pages on the Garman siblings.