Marilyn Monroe was a Hollywood-antique 35 when she attempted, with limited success, to reboot her flagging film career with a star turn in “The Misfits.” Now, at age 42, Meghan Markle — perhaps the biggest modern misfit of all — is attempting to pull off a similar feat. The problem is that the latter-day duchess has no dazzling Arthur Miller-authored script — or any script, for that matter — to work with and may be left taking a page out of the comeback playbook of another troubled blond — Britney Spears — as she seeks fresh ways to restore her quickly fading relevance. 

Ms. Markle has consistently failed to capitalize on her brief career in television, despite the popularity of the discontinued series in which she starred, “Suits.” Her $20 million podcast deal with Spotify collapsed last June after a single season, and things with Netflix aren’t looking too bright either — despite the surprisingly explosive popularity of “Suits” reruns on the platform. Last year, Netflix canceled “Pearl” — “Meghan” means pearl in Welsh — an animated children’s series created by the Duchess of Sussex before it even went into production. Worse, in the wake of months-long Hollywood writers’ and actors’ strikes, the era of lucrative Netflix deals for anyone not on the topmost tier is widely seen as dead.

Yet good old-fashioned celebrity tell-alls still sell well. Prince Harry is said to have received a $20 million advance for his mostly Windsors-bashing memoir “Spare,” published earlier this year. The book generated a tremendous amount of publicity, although it did not win the prince many plaudits at Buckingham Palace. The biggest A-list page-turner now is Britney Spears’s memoir, “The Woman in Me” — according to Investopedia, the book sold a staggering 1.1 million copies in its first week of release and has been Amazon’s most sold non-fiction book for the past three weeks. 

With a long career behind her and a huge fan base, Ms. Spears’s brand recognition far surpasses Ms. Markle’s. The  mix of American teen success story, brash sex appeal, and strong dose of family drama made her book an instant bestseller. Now 41 and fresh from her third divorce, the entertainer appears to be enjoying her renewed place at the center of attention without even having to sing a single note.

For Ms. Markle, by contrast, the struggles are multiplying. Despite cozying up to some big entertainment industry names, the deals have not been coming, which may be why some royal watchers point to the possibility of her penning a memoir as a way to jumpstart the aging duchess’s transition from “Megxit” to  “Meghanaissance.”

Her marriage might be getting old, too. The Duchess is famous for icily moving on from her father, her first husband, her best friend when, her detractors say, they were somehow in the way. Former Vanity Fair editor Graydon Carter — a man who knows a thing or two about celebrity relationships — recently told the Times of London that he “would measure the duration of the marriage [of Meghan and Harry] in years rather than decades.” 

Mr. Carter coolly added that “I think she has run rings around poor Harry and gotten what she wanted: notoriety, money, and a title. His usefulness to her diminishes daily.”

Though that newspaper christened Ms. Markle the “disappearing duchess” on account of her almost studiously low profile in recent months, Ms. Markle knows nothing if not how to bide her time. Cushioned by her royal title and her second husband’s multimillion dollar fortune, she distanced herself from the limelight by residing not at Los Angeles but up the coast at Montecito. She evades the pitfalls of social media by mostly avoiding it altogether. And she waits.

Something she has been less successful at, however, is avoiding is family drama, which, while not on a par with that of Ms. Spears who very publicly fought her father’s oppressive conservatorship, still clouds the public’s perception of her.  Her vendetta with her father is ongoing. And her half-sister, Samantha, reportedly has plans to sue Meghan for making allegedly defamatory remarks about her in a Netflix documentary. 

Such a lawsuit, should it go forward, will prove to be another drain on Ms. Markle’s finances. Maintaining, staffing, and securing a Montecito mansion with a market value north of $15 million is another. Add to that a lifestyle that includes taking private jets to rock concerts at Las Vegas and a more or less permanent falling out with the British royal family, and the pressure for Ms. Markle as well as her spouse to do something with their lives more profitable than pouting about them grows. 

Ms. Markle, according to royal biographer Angela Levin, “doesn’t like losing, she likes to win, feels enormous bitterness and resentment towards the Royal Family for not letting her modernize the Royal Family.” The opportunity she must have seen in Harry, that of woke-ifying the sclerotic Windsors and making herself hugely famous and rich in the process, is no longer an option.

And to paraphrase the title of an  iconic song from Ms. Spears’s extensive catalog, at this point Ms. Markle may be too “toxic” for anyone to care — at Hollywood, London, or even within the high walls of her own ostentatious California manse.