The appeal of the Japanese title Hero seems straightforward enough.
Cast evergreen idol Takuya Kimura as a maverick prosecutor who will dig out the truth of a case regardless of the obstacles in his way. And make sure he looks good while doing it with his luscious locks, eye-catching orange down jacket and spiffy boots.
It is a formula that has worked well for more than a decade.
The first series in 2001 was the most-watched that year and it broke records with an average audience share of over 34 per cent. The big-screen spin-off in 2007 was the third-highest grossing film of the year with 8.15 billion yen (S$96 million) in takings. A second season of the series aired in 2014 and the new movie Hero 2015 topped the domestic box office in its first two weekends in July.
Hero 2015 is showing in cinemas here.
In an e-mail interview, though, Kimura, 42, offers a different explanation for the enduring popularity of the show even though the job of prosecutor is an extremely specialised one that might not be easy to relate to.
He notes: "Despite the actual meaning of the title, the movie revolves around a group of people with no special ability or powers whatsoever. It is about how people who are so passionate about what they do that they become a 'hero' in their own right."
By now, Kimura is strongly associated with Hero and he can slip into character as easily as slipping on his trademark down jacket in the series.
"It really helped that Kohei Kuryu is a character who is very firm and steady. There is nothing much to think about when you play him. You will always tell yourself, 'If it were Kuryu, he would definitely do this,'" he says.
At the same time, he takes on board what the director wants. It helped that director Masayuki Suzuki had also helmed the first series of Hero and previously worked on one of Kimura's early hits, the iconic idol drama Long Vacation (1996).
Adds Kimura: "The director approves most of the things I do to portray this character. By trusting his decision and allowing myself to be led by him, I managed to work to the best of my ability."
It so happens that another Long Vacation alumnus stars in the Hero franchise. Actress Takako Matsu played Kuryu's paralegal assistant Maiko Amamiya in the first series and in the 2007 movie. After being absent from season two, she returns in Hero 2015 as a prosecutor in another district.
The chemistry between Kimura and Matsu is definitely part of Hero's appeal for many fans.
Part of it is the contrast between their characters - Kuryu is dogged and something of a loose cannon; Amamiya is prim and proper - and part of it is that so much between the two is left unsaid.
Kimura, who has two daughters with his pop idol wife Shizuka Kudo, muses: "Kuryu is a person who does not understand his own attraction to women, he gives out signals that he doesn't even feel himself. In other words, he also doesn't seem to be very receptive of signals given by others to him."
Series such as Friends (1994 to 2004) and The X-Files (1993 to 2002) have successfully teased fans and kept them guessing about "will-they-or-won't-they" couplings over the course of many seasons.
Kimura could well be taking a cue from them when he adds: "The relationship of these two persons, if it were to be properly finalised, may lead the story to become sort of boring."
• Hero 2015 is showing in cinemas.