A newly discovered work by a Japanese literary giant is, by default, a thing of delight. The joy of surprise may forgive lesser quality — often the reason why parts of an oeuvre aren’t published — yet I am thrilled to report that Yukio Mishima’s novella “Star,” to be published posthumously on April 30, isn’t merely a treat for completists, but a happy reunion with a genius.

Star, by Yukio Mishima, Translated by Sam Bett.

80 pages

NEW DIRECTIONS PUBLISHING, Fiction.

The slim volume — not to be confused with “A Beautiful Star,” another untranslated Mishima story — first appeared in 1960 in the Japanese literary magazine Gunzo. Most likely, Mishima wrote it either during or shortly after filming “Afraid to Die,” a yakuza potboiler that marked his first starring role in a movie (in addition, Mishima wrote the lyrics to the theme song and sang it himself). Mostly forgotten now in Japan, “Star” owes its English debut this week to a growing appetite for global ficiton.

“More and more, readers in the English-speaking world are turning toward translated literature, and Japanese fiction remains a favorite,” says translator Sam Bett, who had considered tackling “Kyoko’s House,” yet another untranslated Mishima, before discovering “Star” in a university library. “What keeps this particular story relevant is its fixation on the cult of youth. This is a book written by a celebrity about celebrity. It is fiction, but the pressure and corrosiveness of fame feel real.”

The plot follows Rikio “Richie” Mizuno, a volatile young actor with shades of James Dean. It’s the early 1960s, the heyday of the Japanese film industry, when eccentrics and madcap artists were churning out entertainment. Richie is a handsome idol, thronged by adoring fans as he shoots a yakuza revenge flick. In secret, however, he is repelled by his empty life, sapped by the mindless worship of his followers.

“I was their model and their aspiration, the mold that gave them shape,” Mishima writes. “My physique was rugged and my build was solid, but the old power was escaping me. Once a mold has cast its share of copies, it cools and loses shape and is never strong again.”

With his assistant and lover Kayo, a silver-toothed older woman “drunk off her own ugliness,” Richie makes fun of admirers and actresses, finding release in sexual role play. Adrift in the make-believe, he starts losing his grip on time and reality, when a new terror looms in the mirror: the specter of his own aging.

It takes barely a page to recognize Mishima territory, a dreamscape of haunting motifs: Tortured narcissists! Violent fantasies! Sadomasochism with middle-aged women! And most of all, that recurring curse — the worship of youth and “the sin of growing old,” which strikes Richie with fathomless terror.

A new element in “Star” is the musings on fame and personal branding, which may apply to the author himself. Not by accident, the story is told in the first person, a device Mishima seldom used after his early work of fiction, “Confessions of a Mask.”

“I think ‘Star’ exists at a turning point, where Mishima was unsatisfied with literary celebrity and set his sights on superstardom,” says Bett. “This is when he took up bodybuilding, and soon he was wearing skintight polo shirts and sitting for elaborately staged photo shoots. Until then, Japanese authors had been famously reclusive, photographed in their studios, surrounded by bookshelves and piles of manuscript paper. Before long, we have Mishima photographed in a loincloth, gripping a katana sword, barefoot in the snow. I think ‘Star’ is where that Mishima was born.”

The pivot was also literary. In the writer’s oeuvre, “Star” followed the tame “After the Banquet” and led to the epic volcano that was “The Sailor Who Fell from Grace with the Sea.”

The prose here is classic Mishima: hypercharged and manically subjective, with spurts of poetic delirium. Thanks to Bett, however, a feisty American idiom is sprinkled throughout the dialogue, which matches the movieland backdrop. Thus, a screen test is called a “shitshow,” and a crewmember, observing Richie flirt with a starlet, comments cheekily: “Hubba hubba! Tea for two!”

Mishima’s language, often arcane in Japanese, is famously hard to convey in English. Bett takes an open, holistic view, holding that nothing is ever wholly lost in translation. You may have to let go of some nuance, but there are chances to be creative.

“One challenge was the name of the main character,” Bett recalls. “In the original, the actor is named Yutaka, which means “fertile,” in the conspicuous manner of names like Grace. I opted to rename him Rikio, in part so that his nickname could be Richie, which lets English readers access the symbolism. In the 1960s, it wasn’t uncommon for Japanese actors to use American nicknames as stage names. And then Rikio half rhymes with Takeo, the name of Mishima’s character in ‘Afraid to Die.'”

The skillful translation aside, “Star” may pave the way for more Mishima discoveries. Bett, who currently works on fiction by Mieko Kawakami, hopes that if readers enjoy the novella, publishing houses will take a chance on more untranslated Mishima works.

“Quite a few of his novels, much more than most people realize, haven’t been translated into any European language,” says Bett. “There is a lot more to Mishima than the late 1960s pontificating muscleman. He was a writer with quite a few sides, including a significant body of queer fiction. There’s lots of work to do!”