Tokyo Vice‎. When Jake Adelstein got hired in the early 1990s by the Yomiuri Shimbun, Japan’s biggest daily, he was thought to be the first American to pass the newspaper’s rigorous entrance exam. It took him five years of concentrated language study to get that far; even then, it was a prodigious achievement.

Ansel Elgort, who plays the journalist in the HBO Max series “Tokyo Vice,” which is loosely based on Adelstein’s 2009 memoir of the same name, had to make do with four weeks of intensive Japanese classes. That’s presumably four more than Sean Connery spent preparing to play a Japanese expert in “Rising Sun” in 1993.

Still, faking it in a foreign language is a tricky business.

Speaking during a busy day of media interviews to promote the show, Ken Watanabe — who stars opposite Elgort as Adelstein’s police detective mentor, Hiroto Katagiri — recalls the learning curve he faced when he took his career abroad two decades ago.

The actor, now 62, was already an established screen and stage star in Japan when he was cast opposite Tom Cruise in Edward Zwick’s “The Last Samurai” (2003), picking up