Tom Selleck on his Jesse Stone character

If you enjoy Tom Selleck as Jesse Stone, catch him while you can.

That's the word from the Emmy-winning actor. Having wrapped up the sophomore round of his CBS police drama "Blue Bloods," which is returning this fall for a third season, he's also appearing in the network's eighth film about novelist Robert B. Parker's small-town loner New England sleuth. "Jesse Stone: Benefit of the Doubt" airs Sunday at 9 p.m., and Selleck says it could be his last time in the role . . . for CBS, anyway.

"Bless them, they've done eight of these that always perform far above what's normally in the time slot," he acknowledges. "but they are constantly perplexed [by the thought], 'We're not in the two-hour-movie business.'

"That being said, that's not the end of Jesse, or at least I don't think so. There are a lot of other entities, whether cable or even feature films, but this is most likely the last one on CBS. I'm not done with the character, though."

Selleck, who's also executive producer and co-writer, again delivers a mystery that stands on its own while building in familiar touches for fans of his previous "Jesse Stone" tales. One blows open the story, literally, putting Stone back in the job of police chief of Paradise, Mass.; among returning co-stars are Kathy Baker, William Devane, Gloria Reuben, Saul Rubinek, William Sadler and Stephen McHattie.

"They're hard movies to do, and they're expensive," Selleck says. "I'm almost proud to say that with the last four, I've had to put in some of my own money to get them made.

"There are a lot of surprises in this one. We felt it was time for Jesse to try to put his universe back in order. We've done movies where there's been real jeopardy to that world, and if we do our job right, you get inside Jesse's head. And once you're inside, you're along for the ride."

That ride can take turns toward spurts of shock and violence, as with an on-screen probe of two corpses that marks Stone's official return to police work in "Benefit of the Doubt."

"We've pushed that envelope," Selleck says, "but I'm finding out over time that that's how a lot of cops work. Nobody's trying to exploit anything here."