Set along the U.S.-Mexico border, Go for Sisters touches on themes that have been central to John Sayles' work for decades: class, race, power, and corruption. The indie stalwart departs from his recent playbook by placing a rather conventional plot, rather than political point-making, firmly in the foreground. It's a plot that never takes hold, a mystery devoid of suspense.

Amid all the whodunit busy-ness of the story, with its drugs, guns, kidnappings, and human trafficking, Sayles' real interest is character. However implausible their surroundings, the three lead performances give the film its quiet center.

There's a humorous touch of Nancy Drew, reconceived as a vehicle for middle-aged characters of color, in the unlikely sleuthing by an odd trio of Angelenos. Their urgent road trip to Tijuana is orchestrated by parole officer Bernice (LisaGay Hamilton), whose estranged son has gone missing and is apparently in deep water with unsavory associates. She enlists street-smart Fontayne (Yolonda Ross), a long-unseen friend from high school who turns up in her caseload one day, and the bloodhound instincts of Freddy Suarez (Edward James Olmos), a former police detective who's losing his sight.

Their direct inquiries in shady quarters are no more credible than most of what transpires, with each tip or threat leading to another in a tension-free domino effect of pulpy character types.

But the actors' unforced chemistry defies the artifice. Olmos' delectable hamminess and Hamilton's unfussy performance convey volumes. Ross, guarded and resilient, is a revelation. Fontayne and Bernice, whose renewed but tentative friendship is the heart of the matter, mirror to each other what might have been, and what might still be.

Go for Sisters (** out of 4 stars)

Written and directed by John Sayles. With LisaGay Hamilton, Yolonda Ross, and Edward James Olmos. Distributed by Variance Films.

Running time: 2 hours, 3 mins.

Parent's guide: Unrated

Playing at: AMC Cherry Hill 24