Stone, now the suspended police chief, continues to investigate a murder as he battles his own demons.
On "The Early Show" Wednesday, Selleck said that, as the film's co-writer and co-executive producer, he wanted to make it looked like a feature, not a made-for-TV movie.
"I don't think there's enough character-driven stuff on TV. This is about the people. I mean, our plots are important -- they're mysteries -- and I think they're good mysteries, but without the people and Jesse is a very watchable guy, he's a mess, so he has issues. He's very flawed, but the audience sees he's a pretty decent guy and they root for him as he keeps making mistakes."
Selleck said Jesse is a good basis to start a show.
"I always felt this character had legs when I tried to sell him to my boss, Les Moonves (president and chief executive officer of CBS Corp.)"
Selleck has finished the seventh installation of the Stone series called "Innocents Lost," and is currently writing the script for the eighth film.
But Selleck says he never had aspirations to write. However, he says because of his close connection to the character he seems to "get it" because "they still seem to be working."
Selleck, himself, also seems to be working, because, as "Early Show" co-anchor Maggie Rodriguez observed, he's still acting 30 years after "Magnum, P.I." began its eight-year run.
She said it looks like he never ages.
Selleck replied jokingly, "I do."
He added that in show business, the trap for many people is being who you were 20 years ago.
"You're going to have a very short career," he said. "I think you've got to be comfortable with who you are."
For more with Tom Selleck, click on the video below.
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You can see "Jesse Stone: No Remorse" on Sunday, May 9, at 9:00 p.m./8:00 p.m. Central, on CBS.