PHOTO BY ALEXANDRO BOLAÑOS ESCAMILLA / LIONSGATE

By the time a franchise reaches double digits — a rare honor, if a somewhat dubious one — changing the formula is usually off the table. Yet “Saw X,” the 10th chapter of the gory horror franchise, not only dispenses with many of the series’ hallmarks, it actually makes its villain into a hero.

Yes, I’m referring to Jigsaw. The guy who makes all the torture machines. He’s the good guy in this one. You can imagine how evil the villains must be.

John “Jigsaw” Kramer (Tobin Bell) has received the brian-cancer diagnosis that will lead to his death. When a fellow survivor tells him about a cutting-edge treatment offered at a fly-by-night clinic in Mexico City, Kramer travels to meet a reassuring doctor (Synnøve Macody Lund) and her team of surgeons, who promise a miracle cure.

Before long, however, Kramer realizes he’s been had; the treatment was an elaborate ruse and the doctors have vanished. With a little help from his friends, Kramer tracks down the con artists and decides they’re in need of a little extreme education.

This isn’t the first time a Saw film has encouraged audiences to root against the nominal victims; a previous franchise high point, “Saw VI,” put a heartless health-insurance executive through the ringer. This is, however, the first film in the series without a police-procedural element; usually, a team of hapless detectives is racing against the clock to find Jigsaw’s trap before it’s too late. In “Saw X,” there’s just Jigsaw and his even more nefarious adversaries — making for a more linear and structured story than previous installments.

Will series devotees be turned off by a different approach? Perhaps; I’d hope, however, that they would recognize the benefits of having much more of Bell, an undeniably excellent actor who has been necessarily sidelined for many of the films. (The Jigsaw character — spoiler, I suppose — died way back in “Saw III,” and has mostly appeared in flashbacks since. “Saw X” takes place before the events of “Saw III.”)

Will more casual audiences be troubled by the urge to cheer for such a violent protagonist? Eh, everyone loves an anti-hero. And familiarity breeds fondness; even after nine films of mayhem, Jigsaw feels a bit like an old friend.

My Rating: 7/10

“Saw X” is now playing in theaters.