Part torture-porn, part whodunnit, Chris Rock’s Spiral succeeds rather well at one its genres.

Released Friday, Spiral, while not a true sequel to the Saw movies, is set in the same universe. Rock, who pitched the idea for the film to Lionsgate Pictures, ended up as executive producer of the film. Darren Lynn Bousman, who helmed Saw II, III and IV, returns to direct this one. Josh Stolberg and Pete Goldfinger, who co-wrote Jigsaw, are among the other franchise veterans who are back on board.

After an amusing cold open designed to show that Rock’s character Zeke Banks is a cop who doesn’t play by the rules, the grisly fun begins. An officer attempting to foil a purse-snatcher finds himself in the clutches of the killer, and trapped in an elaborate torture device watching the killer in a pig mask on a strategically-placed video monitor offering to play a game.

Jigsaw 2.0 (the character is never named) as ever, wants to play a game, offering the victim the familiar choice that’s not really a choice: escape the death trap by giving up a crucial body part, or die a horrible death. It should surprise no one that this death (and almost every one afterward) is both inevitable and presented in explicit, extensive and gory detail.

Banks, after being reprimanded for his solo escapade, earns himself a rookie partner (Max Minghella, The Handmaid’s Tale) and the lead role on the case looking into their colleague’s death. The film leans pretty hard on anti-police sentiment; Banks turned in his dirty-cop partner and became a pariah in his precinct, taking a bullet when none of his colleagues came when he called for back-up. It soon becomes obvious to Banks (and the rest of the force) that the killer is targeting only cops.

The one person on Banks’ side is his father Marcus, played by Samuel L. Jackson, who was the former chief of police. Jackson’s character sticks around long enough to (possibly) become a red herring, then he vanishes. It’s up to Chris Rock’s character to figure out who is brutally (and easily) dispatching all the dirty cops.

The killer leaves behind taunting videos and body parts culled from the victims and the cops peg the killer as a disciple of the deceased Jigsaw. The police are never able to use their clues to get ahead of the killer, nor do they take steps to do anything to keep each other safe.

As a whodunnit, Spiral works if you don’t pay any attention to the multitudes of clues presented. If you are just there to enjoy the kills, they are in good supply; human beings are rent apart or otherwise dispatched in unsparing and gruesome detail using elaborate contraptions. Speaking of details, pay attention and you’ll see and hear references to the stars’ previous films like Jackson’s Pulp Fiction and Rock’s New Jack City.

Rock makes a fine lead, though more successful when he gets to be funny (he has a tendency to use a thousand-yard-squint to convey his character’s deep distress.) Jackson is terrific, of course, but his is a limited role. Minghella is as great here as he is in Handmaid’s Tale, and just as hard to pin down: is he good or bad? You’ll have to watch to the (abrupt) end, which definitely sets up sequel possibilities for the franchise.