Russell Crowe plays a cop remembering things that might best remain forgotten in a more sturdy-than-inspiring thriller about a murder, a wrongly-accused death row inmate and more than one suspect who’d prefer to let “Sleeping Dogs” lie.

Based on a novel by E.O. Chirovici, it sets up as a twisty tale in the “Memento” style. A man whose memory is addled by early onset Alzheimer’s, forced to label everything in the house, from the “front door” down to his microwave meals with taped child-appropriate instructions, is called upon to save the life of a convict (Pacharo Mzembe) who claims he’s innocent, and that the former detective either knew that back when, or didn’t care enough to dig deep and clear him.

Wearing a stocking cap to hide his “experimental treatment” scar, Roy flashes back to visits to his doctor, who tells former detective Roy Freeman his years-long alcoholism is “a common trigger for Alzheimer’s,” but that the surgery, the implants and vigorously exercising his mind — puzzles, memory-jogging — could turn him around. Roy will meet up with his old partner, open case files and revisit a past that didn’t exactly cover him in glory.

He was fired, with cause. He was a “loyal” cop, which suggests that “We look out for our own” ethos that is the core of much police corruption. And there were plenty of motives and suspects floating around this womanizing, manipulative, credit-stealing college professor (Marton Csokas) who got himself beaten to death.

The desperation of the condemned man is tinged with rage. You’d be angry too, if your only hope was a disgraced cop whose memory is out to lunch, perhaps never to return.

Tommy Flanagan plays Jimmy, the old partner who admits “We all drank on the job, back then,” as if that’s some consolation to Roy. Sure, he’ll pitch in. Or will he?

Harry Greenwood is a writer whose true crime memoir recalls the murder, his college days working with that dead professor, and obsessing over the creep’s brilliant polymath research assistant, played by Karen Gillan.

Gillan’s Laura Baines is painted in femme fatale shades. Like others he meets, she remembers Roy even if Roy cannot remember her, or the case, very clearly.

He’s acting on “just a feeling,” he admits. “That’s all I’ve got to go on these days.”

The more he digs, the more he remembers and the more stones he turns back over, or figures out that he never turned-over in the first place.

Adam Cooper, graduating from screenwriter (“Assassin’s Creed,” “The Transporter Refueled”) to director and co-writer, barely maintains his directing debut’s forward motion, which mutes its impact. Too many shots of Crowe’s Roy pondering this or that, sometimes jarred by a flashback, make “Sleeping Dogs” a fairly sleepy affair.

I liked the way Roy relies on what he used to do by rote, methodically questioning, reading up and extrapolating clues, listening to his instincts about who may or may not be involved, tracking the threads of the plot in post-its notes and the like.

Memory loss or not, these are the muscles Roy used to exercise. Now, if he could just figure out which flashbacks are suppressed or lost memories and which are hallucinations, he’d be cooking.

The poor pacing and a platoon of peripheral characters weigh the picture down and cheat the viewer of the chance to get ahead of the plot.

But Crowe’s guarded, meditative presence more or less holds this cluttered, convoluted tale together.

Flanagan and Csokas show us flash.

And Gillan takes a good shot at showing us a woman with problems, a past and a hard-to-pin-down place in all this, perhaps out of guile, or perhaps owing to fear of what waking these “Sleeping Dogs” will do to her, Roy, the past and all of their futures.

Rating: R for violence/bloody images, sexual content and language.

Cast: Russell Crowe, Karen Gillan, Tommy Flanagan,
Pacharo Mzembe, Harry Greenwood and Marton Csokas.

Credits: Directed by Adam Cooper, scripted by Adam Cooper and Bill Collage, based on a novel by E.O. Chirovici. Released by The Avenue.

Running time: 1:50