Rumor has it that NHK’s taiga drama series — year-long Sunday night staples — may be cursed. Taiga (literally “big river,” but here refers to a historical saga) has been an institution since the first installment launched in 1963. As one of NHK’s best-known shows, taiga has traced epic moments in Japanese history, often in impressive depth and detail. Generations of Japanese students (including this writer) plowed through their history exams with knowledge garnered from the shows.

But trouble seems to be brewing. Last year’s iteration, “Idaten,” which was the first to draw on more modern times by looking at Japanese Olympians, was plagued by two things: the arrest of actor Pierre Taki midway into the series, and ratings hitting an all-time low. Taki was a principal cast member, and NHK reshot his scenes with another actor. The ratings, however, were beyond the broadcaster’s control.

Unfortunately, history seemed to repeat itself ahead of this year’s series, “Kirin ga Kuru” (“Awaiting Kirin”), when actress Erika Sawajiri was arrested in November for drugs offences. NHK producers announced a fortnight’s delay to the start date and reshot all of Sawajiri’s scenes, along with advertising and promo footage. NHK had already finished taping the first 10 episodes and, as with “Idaten,” it had to scrap everything and start over. Haruna Kawaguchi, a 24-year-old film and television actress, took over Sawajiri’s role as Kicho, the wife of the warlord Oda Nobunaga (1534-1582).

In a complete about-face from its predecessor, “Kirin ga Kuru” takes audiences to 16th-century Japan, when the nation was fractured from a century of clan wars. The titular kirin is a mythical creature that heralds the arrival of a benevolent ruler, and the drama implies that this ruler is the protagonist, Akechi Mitsuhide, a mild-mannered, bookish colonel who abhorred the ruthless tactics of his boss, Oda Nobunaga.

Mitsuhide rose to prominence under Nobunaga’s command, but later betrayed him in the attack on Honnoji temple, one of the most dramatic (and dramatized) incidents in Japan’s history. Up to now, any taiga set in this period came from Nobunaga’s perspective. “Kirin ga Kuru” marks the first time NHK has put Mitsuhide in the spotlight.

So far, so good … or perhaps not. Sawajiri’s absence has left a gaping hole, and critics who have seen Kawaguchi act on set are saying that her performance is too flimsy. Though NHK is surrounding the series with positive hype (the first taiga in the Reiwa Era, the first to be shot in 4K, and the return of star scribe Shunsaku Ikehata, penning his first taiga in 30 years), NHK watchers say that a cloud of anxiety has descended on the set, mainly over Kawaguchi’s perceived inadequacy.

On a positive note, the role of Mitsuhide has gone to Hiroki Hasegawa, a skilled actor who has worked on a taiga series before. Despite that, if rumors are to be believed, Ikehata has requested the presence of an older, star actress to ramp up the atmosphere on set. Word is it could be veteran Takako Matsu, but how she will appear and whether she can break the curse remains to be seen.

“Kirin ga Kuru” airs at 8 p.m. on Sundays from Jan. 19 on NHK G.