Hollywood’s Favorite Samurai Reimagines ‘Shogun’

When preparing for his role in “The Last Samurai," Sanada helped instruct co-star Tom Cruise in wearing a kimono and wielding a sword. While playing an android samurai on HBO’s “Westworld" he weighed in on the look of robot geishas. Even on “Mortal Kombat," based on an over-the-top videogame, the movie’s most seasoned star routinely inspected costumes in a process his castmates called “Sanada time."

Keanu Reeves says he’s relied on Sanada as an actor and an adviser—for the protocol of a suicide ritual in 2013’s “47 Ronin" and for the way their characters held cups of tea in a somber scene in last year’s “John Wick: Chapter 4."

“His standard of excellence is quiet but profound. You don’t want to let Hiro down," Reeves says, describing his friend’s on-set sign of approval as a nod and an affirmative “mmhm."

Now, at age 63, Sanada’s role as arbiter of authenticity is official. For “Shōgun," a new adaptation of the famous saga set in feudal Japan, Sanada helped lead the project as both a star and a producer.

“Finally, after 20 years in Hollywood movies, I got a title," Sanada says at a Japanese garden in Los Angeles, his home base for the past two decades.

“Shōgun," premiering Feb. 27 on FX and Hulu, is the most expensive production ever for Disney-owned FX. It’s a lavish and risky retelling of a title that looms large in pop culture. In James Clavell’s 1975 novel, an English sailor navigates a labyrinth of Japanese warlords, Catholic priests and romance with his translator. Clavell’s bestseller led to a 1980 NBC miniseries that became one of the highest-rated broadcasts of all time.

Starring Richard Chamberlain, the miniseries broke ground by shooting in Japan and showcasing a cast including Toshiro Mifune, a legend from Akira Kurosawa’s films. But there were blind spots. Among them: Japanese dialogue with no subtitles, a choice that underscored the perspective of Chamberlain’s character while rendering the Japanese characters alien.

For Sanada, the effect the miniseries had in introducing Japanese history to America was more significant than the show itself. He and his collaborators spent the last five years on a new version that would rebalance the story’s East-meets-West theme, immerse viewers in the Sengoku period of 1600 and do justice to the complex narrative of the novel. Sanada brought his copy to the interview, a paperback Japanese translation bristling with his colorful bookmarks.

On screen, Sanada plays Lord Yoshii Toranaga, an embattled leader who uses cunning and misdirection to fight for the survival of his clan and the future of Japan. Behind the scenes, the producer oversaw masters of wardrobe, gesture and weaponry. He put a final eye on details down to the nuance of subtitled Japanese dialogue, which makes up nearly 70% of the language in the series.

Sanada describes “Shōgun" as the culmination of an acting career that spans more ninjas and samurai than he can count and a stint with the Royal Shakespeare Company.

He is low-key when talking about his trajectory. He seems more eager to discuss his fishing hobby than his physical training regimen. He chuckles about the “old parts" of his body that have weathered countless fight scenes, especially his ankles, which Sanada soothed in his “Shōgun" trailer using an ice-therapy machine that Reeves sent him.

“I put everything into this show which I’ve learned before," he says. “So hopefully it will be a big footstep toward the future."

An East-to-West Career

Born in Tokyo in 1960, Sanada started on his show-business path as a 4-year-old model. Acting lessons followed, along with his first movies as a child actor, co-starring in yakuza gangster pictures with action hero Sonny Chiba.

In the Japan Action Club, a troupe coached by Chiba, Sanada polished his martial-arts skills for the screen. He also did formal training in the kendo style of sword fighting and other disciplines. On the “Shōgun" set, he carried a fan that belonged to his former teacher in traditional Japanese dance.

Sanada’s fame rose with the 1970s and ‘80s boom in Japanese martial arts movies (“The Shogun Assassins," “Samurai Reincarnation," “Ninja in the Dragon’s Den" to name a few). But he belonged to a postwar generation who had global ambitions. Sanada’s list of inspirations included Al Pacino and Jack Nicholson.

In 1988, he performed as Huckleberry Finn in a Japanese-language production of the musical “Big River" alongside Tony winner Ron Richardson. He dove into the deep end of performing in English when he played the Fool in an RSC production of “King Lear" in London in 1999. Around the same time, Japanese audiences saw him in the influential horror movie “Ringu," later remade in Hollywood as “The Ring."

“It was always finding the role for the next step, finding the higher hurdle," Sanada says. “Every time, I felt it was a debut."

A crossover came with a drama nominated for best foreign language film at the Oscars. In 2002’s “The Twilight Samurai," directed by Yoji Yamada, Sanada played an impoverished member of the warrior class who wants to farm, not fight. The film is an example of how historical knowledge has been passed down in Japan—not only through scholars and museums, but also through the filmmakers who’ve been re-creating the nation’s ancient culture on screen for a century.

“I had great masters in my career," Sanada says. “They were the generation of the golden era of Japanese film and worked with those legend directors—Akira Kurosawa, Yasujiro Ozu. These high-class crews taught me a lot. That’s my treasure." On multiple occasions, Sanada has played real-life historical figures that fictional “Shōgun" characters were based on.

Sanada’s double duty as a Hollywood adviser began with “The Last Samurai," the 2003 epic that introduced him to U.S. audiences. He played Ujio, who schools Cruise’s Civil War veteran in combat. In real life, Sanada helped massage the fight choreography throughout the movie to make it more authentic to 1800s Japan. The results showed in a standout scene in which Sanada and Cruise clash with wooden swords in the rain.

“Sanada was leading the dance in that moment," director Ed Zwick recalls. “That is one of the most remarkable displays of control and stage fighting that I have or anybody will ever see. One slip on that wet ground in a torrential rain and we would have been down one movie star."

In “47 Ronin," a fantastical take on the samurai genre, Sanada adjusted his own sword moves to make his fighting partner’s look better, Reeves recalls. “I’d be slow, so he would create these little gestures and flourishes so it would take up time and look quick and intentional," he says.

Despite Sanada’s growing reputation as a cultural fixer on sets, being an actor who requested corrections from directors and department heads made him anxious about overstepping or hurting people’s pride, he says.

Finding Balance in ‘Shōgun’

As a “Shōgun" producer, Sanada had a small army of Japanese specialists answering to him on location in British Columbia, which stood in for medieval Japan.

Series co-creators Justin Marks and Rachel Kondo recall Sanada’s push to hire an expert dedicated to tying the obi sash for the robes that actors and extras wear in the show. The studio initially said no to what seemed like an unnecessary expense.

“By the third day of production," Marks says, “that guy was on a plane coming out to work with our crew" to teach them to costume actors more quickly and properly.

“Shōgun" features Sanada’s dramatic chops more than his action skills. As Toranaga, he maneuvers through a shifting maze of rivals, family members and uneasy allies. The ensemble includes famed Japanese actors such as Tokuma Nishioka and Tadanobu Asano. Cosmo Jarvis plays the Englishman, John Blackthorne. Anna Sawai plays his translator Toda Mariko, a highborn lady with a stained family history.

In the show, Lord Toranaga elicits roars of loyalty from his troops. Sanada had a more subtle but similar effect on the “Shōgun" crew and cast, says Marks, who oversaw the production.

“He knows that when he shows up that, especially for the Japanese actors, their eyes are on him, and not just when he’s in character," he says, adding, “We wanted to bring that element to the part because Toranaga is someone who is always surrounded, even when he’s alone."

Sanada says he feels a duty to represent Japan on the world stage and bridge cultures. In “Shōgun," he adds, “everything is linking."

When he arrived at a “Shōgun" party hosted by FX at a recent press event in Pasadena, Calif., Sanada made a beeline for the handmade costumes displayed under spotlights around the room.

He eyed one of his own wardrobe pieces, a ceremonial hitatare robe of gold, copper and brown, which matched the colors of the pocket square he wore that night with his suit. Noticing an imperfection—an obi belt that was a trifle too exposed—Sanada reached out and adjusted the costume himself.

Write to John Jurgensen at John.Jurgensen@wsj.com