In a four-decade career, Haruhiko Arai has become an acclaimed scriptwriter with credits that include “Vibrator” (2003), “It’s Only Talk” (2005) and “Kabukicho Love Hotel” (2014), three of the best films by his frequent collaborator, the director Ryuichi Hiroki.

Arai also edits and publishes “Eiga Geijutsu,” a film magazine notorious for its annual “Best Ten” and “Worst Ten” polls, with the latter attracting more attention for its contrarian picks, including films by Naomi Kawase, Hirokazu Kore-eda and other internationally noted Japanese auteurs.

Last year Arai was played by Kisetsu Fujiwara in “Dare to Stop Us,” Kazuya Shiraishi’s 2018 drama about renegade director Koji Wakamatsu and his circle in the late 1960s and early ’70s.

In the film, the young Arai is a cynical intellectual who scripts the pornography that keeps Wakamatsu’s little movie factory financially afloat. In real life, Arai went on to pen scripts for dozens of films, erotic and otherwise, including the 1979 Tatsumi Kumashiro classic, “A Woman With Red Hair,” and the 1999 Rokuro Mochizuki gangster action flick, “Minazuki.”

Arai has also directed three films of his own, the latest being “It Feels So Good,” a drama of illicit love based on a Kazufumi Shiraishi novel, which opened on Aug. 23.

In the film, Tasuku Emoto stars as Kenji, a recently divorced and unemployed man who returns to his hometown of Akita to attend the wedding of Naoko (Kumi Takiuchi), a cousin and former lover. She invites him to share her bed for a last night of passion, but, when he accepts, one night stretches to five until Naoko’s fiance returns from a business trip — and the couple must make a decision.

Away from the film set, in the office of the film’s distributor, Arai is like a more soft-spoken, if still sharp-tongued, version of his character in “Dare to Stop Us.”

Asked why he decided to direct “It Feels So Good,” he gets right down to specifics.

“The budget wasn’t very big,” he says. “Also there are only two main characters, which is in the range of what I can do.”

When I say that the film reminds me of “In the Realm of the Senses,” the 1976 Nagisa Oshima classic that also depicts lovers engaged in days-long erotic games, Arai shakes his head.

“I don’t like that film so much, so I wasn’t influenced by it,” he says. “Foreigners may think that way, but for me (“It Feels So Good”) is closer to films of my own like ‘A Woman with Red Hair’ or ‘Vibrator.'”

However, both Oshima’s film and Arai’s unfold against a backdrop of larger events, I counter — World War II in the former case, the Fukushima nuclear disaster in the latter. Why, I wonder, did Arai shift the setting from the Fukuoka of the novel to Tohoku?

“One reason was I wanted to shoot the Nishimonai Bon Odori dance (in Akita Prefecture),” he says. “Another is that in Tohoku, only Akita Prefecture was unaffected by the (Great East Japan Earthquake and subsequent tsunami and nuclear disaster). So it was kind of left out. Being left out of a disaster is a little strange, but also lucky. It relates somewhat (to the film’s story) so I wanted to include it.”

He also made his two principals younger than the around-40-year-old man and 35-year-old woman in the novel.

“It was hard to get actors of those ages to appear in the film,” Arai says. “Especially actresses in their 30s — they all turned us down.”

One possible explanation: The sex scenes, which are explicit and frank enough to earn the film an R-18 rating.

One thing Arai did take directly from his source material is its theme of incest.

“In the novel the woman’s mother dies young and she is raised by the man’s family,” he says. “They are raised as brother and sister. So they are not just cousins, but a lot like siblings. For them sex brings up the incest taboo. They feel they are doing something wrong. The man especially has long thought that the wedding (of his cousin) means they will have to part.”

But the woman, Naoko, challenges this taboo by seducing the man, Kenji. This, Arai admits, is unusual in a culture that “teaches women to believe that they don’t have sexual desire. But of course they do. So they can also make the first move, though it’s not easy.”

Similarly, Arai had the heroine of “Vibrator” seduce her truck driver lover.

“Audiences abroad liked ‘Vibrator’ because they liked the scene of woman reaching out to the man,” he says. “But in Japan some strange-thinking women said that the scene of the woman making the first move was just male desire talking.”

His lead actress in “It Feels So Good,” Kumi Takiuchi, had been relatively unknown before starring in Ryuichi Hiroki’s 2017 drama, “Side Job.” However, Arai says she “didn’t make much of an impression” in the film and it was not the reason he cast her.

“I just didn’t get that film,” he says. “I didn’t get the story. So it’s a not slam on her performance. I wasn’t happy with the structure of the movie.”

His lead actor, Tasuku Emoto, comes from a prominent acting family — his father is veteran character actor Akira Emoto — and Arai praises his professionalism.

“He’s quick on the uptake. You say something once and he says, ‘I understand.’ But if there’s some explanatory dialogue he doesn’t want to say, he rattles it off in a monotone, as cool as can be. He’s like his father that way.”

Arai also teaches scriptwriting at the Japan Institute of the Moving Image, a film school founded by renowned director Shohei Imamura. Are there any promising scriptwriters among his students, I wonder?

“No,” says Arai flatly. With the advent of digital technology, he says, “It’s easier for film directors to make a name for themselves. But it’s harder to train scriptwriters and launch their careers. Now they start out together with directors, like Kosuke Mukai and Nobuhiro Yamashita. If they’re on their own, it’s hard.”

He also has little good to say about Shiraishi’s “Dare to Stop Us.”

“For those who actually know that era, the way people born after that era shoot it and act it is totally different from the reality.

“But the problem is also with the audience,” he says. “They don’t know the era either. That’s a weak point of Japanese films today — neither the filmmakers nor the audience know anything. For example, the guy who portrayed (director) Masao Adachi didn’t know he’s left-handed. He didn’t study enough. But the kid who played me did his homework. He got the feeling right.”

This, I realize, is almost the first good word Arai has had for anyone since I walked into the room. But he is not bitter so much as “I couldn’t care less” candid.

He leaves me with this parting shot: “You have people who don’t know the history making the films and people who don’t know the history watching them. In other words, idiots make films and idiots watch them. That’s where we are now.”

“It Feels So Good” is now showing in theaters across the nation. For more information, visit kakounofutari-movie.jp.

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