Even the best thrillers allow or invite the viewer to get a step or two ahead, to anticipate what’s coming next, or what might come.

The script usually reveals its mysteries by relying on melodramatic tropes or cliches of the genre. You think, “She’s in a car, ducking,” so naturally “Who will shoot the windows out?”

A big name is cast in what looks like a minor role, and you instantly guess, “Oh yeah, He/She is IN on it.”

It’s taken a lifetime of training for me to not make the little siren noise I hear in my head, every time I expect the police to show up in the not-quite-nick-of-time, signaling the story’s end.

“Traffik” isn’t a very good thriller, and if you aren’t two or three steps ahead of it, much of the time, you need more practice.

But writer-director Deon Taylor’s “Put Paula Patton in Peril” picture has merits. For one, there’s Patton, whom he and his cinematographer give the full “Damn, girl” treatment — extreme closeups of body parts, cleavage, Daisy Duke derriere, classic semi-clad female objectification. It’s why she’s a movie star, so OK, whatever sells tickets.

Taylor lets Patton trot out that “I can’t get hurt again” coquettish thing, the poor little screen beauty who can’t find and hold onto love. It comes with a girlish voice one would have hoped Patton would have shed after “Precious,” but no.

But Patton doesn’t play the passive victim, another plus.

The action beats– fights, chases — are visceral, well-shot and edited. And some scenes are well-staged, with beautifully-composed shots. “Traffik” begins with a whimper but finishes with a flourish.

It’s all the talking, plotting and what-not in between that gets in the way.

Brea (Patton) is an idealistic reporter with completion anxiety. She can’t boil the work down and get the scoop in a timely manner, so her Sacramento Post boss (William Fichtner) has told her “I don’t think there’s a place for you here, any more.”

On her birthday, no less. Yeah, a newspaper would totally do that.

Her man John (Omar Epps) is a car-builder/restorer who surprises her with a trip to the NoCal mountains. The surprise is repeatedly wrecked by John’s old pal Darren (Laz Alonzo), a can’t-stop-talking, rude and tactless sports agent. How Malia (Roselyn Sanchez) puts up with him is anybody’s guess.

John’s all set to pop the question when these two show up.

There’s been trouble on the way. A strung-out, emaciated woman (Dawn Olivieri) scared Brea with her condition when they met in a gas station’s restroom. And John, driving the ’69 Chevelle he rebuilt for Brea, can’t avoid the hassles of a bunch of let’s-start-something biker toughs at the pumps.

The stage is set for a nighttime visit by those folks, plainly involved in trafficking women for the sex trade. “These women are product” may be the most superfluous line in the picture.

A mountaintop mansion with walls made of glass, as one character cracks, is no place to hold off hoodlums.

Poorly written screenplays always have somebody say “Nobody needs to get hurt,” after we and they have seen somebody murdered, right in front of them.

Brea has something the bad guys, led by British Red (Luke Goss), want. Brea might have need of it, too. Leave it to jerk Darren to work everything out.

“I’m a negotiator. This is what I do.”

It takes a whopping 40 minutes for the action to truly begin, and another 20 for things to pick up in earnest. Patton needs her topless love scene, her bikini dip in the infinity pool, her post-coital wear-the guy’s-unbuttoned-shirt moment.

Am I objectifying her? No. The director got to that first.

And even those scenes you can see coming. But there is one genuine surprise, a jarring if touching and not quite appropriate tune on the soundtrack.

Human trafficking is better known by its original name, slavery.

Just as things reach their bleakest and we fret for the womenfolk falling into the clutches of modern day slavers, Nina Simone curls up on the soundtrack. “Strange Fruit,” she sings, the anti-lynching anthem made famous by Billie Holiday.

Did not see THAT one coming, Miss Simone.

MPAA Rating:R for violent and disturbing material, language throughout, some drug use and sexual content

Cast: Paula Patton, Omar Epps, Roselyn Sanchez, Missy Pyle, Laz Alonzo, William Fichtner, Dawn Olivieri

Credits: Written and directed by Deon Taylor. A Summit release.

Running time: 1:36