A timely yet undercooked action-thriller about police corruption and racism, “Black and Blue” cuts to the chase from its very first, promising sequence. Along the beats of Lecrae’s social injustice-themed “Welcome to America,” Alicia West (Naomie Harris) jogs through the middle-class streets of a suburban New Orleans neighborhood, only to be stopped and harassed by a pair of suspicious white cops, interrogating her with excessive force for no reason. It’s not long before the cops realize that “she is a blue,” a part of their team, and let her go; though with palpable arrogance. It’s clear that they would face no consequences, even after illegally slamming one of their own against a fence. Their privilege happens to be standard operating procedure.

It’s a powerful scene, all too real in today’s world where amateur cell phone videos of similar or worse cases of police brutality continue to go viral. Still, its harrowing vigor is rooted not only in its unspoken relevance but also its cinematic tautness — a virtue director Deon Taylor (“The Intruder”) sadly doesn’t manage to seize throughout. While the premise of Peter A. Dowling’s screenplay is ripe with potential and the ensemble — led by an emotionally and physically commanding Harris and Tyrese Gibson, every bit her match in the role of a reluctant ally — is impressively in sync, “Black and Blue” feels imbalanced and overlong, favoring fast and repetitive chase scenes over well-calibrated tension.

And the premise itself is a bit too closely matched with Antoine Fuqua’s far more effective “Training Day,” down to a brazenly re-created bathtub scene that stands as a pointless remake rather than homage. Still, Dowling and Taylor deserve some credit for trading Ethan Hawke’s young, idealistic but inexperienced white male cop for a woman of color, navigating all the contradictory odds stacked against her. In that, “Black and Blue” is at its strongest when it inspects West’s multi-layered intersectionality also teased in the title: a newbie black female cop in stereotypically masculine shoes, not entirely embraced by the diverse community she serves (“She is one of them now,” the neighborhood thinks) and stuck in the midst of a well-oiled machine of white-enabled corruption that also holds people-of-color cops hostage. But the machinations of this avenue go somewhat underexplored, once West finds herself on the run after witnessing (and capturing on her body cam) the homicide of a young black man by police forces.

West learns quickly that she can’t really trust anyone while plotting her escape from fellow officers who put the blame on her and demand her head on a silver platter, a shady criminal group that includes the intimidating Darius (Mike Colter) and the vicious Terry Malone (Frank Grillo). With even her partner Kevin (Reid Scott) bearing traces of ambiguity, she turns to Mouse (Gibson) for refuge, a convenience store owner who wants no part in this escalating crime maze, but lends West a vital helping hand all the same, acting as an intermediary between West and a rightfully angry community about to turn its back on her.

For the most part, legendary cinematographer Dante Spinotti keeps the unimaginative but serviceable action clean and coherent, occasionally recalling the blue-tinted atmosphere of Michael Mann’s “Heat,” which he also lensed. Still, it’s not the sweaty and adrenaline-heavy cat-and-mouse pursuits that pack the fiercest impact here. It’s the quietly played scenes that prove most memorable after the end credits. In one, a young black boy, convinced of West’s guilt, points a gun toward her. Through a pair of others, the uptight but fair-minded Missy (Nafessa Williams) confronts her childhood friend West with her long-standing grudges. In a subtle detail, an entitled cop walks away with free coffee and snacks from Mouse’s modest shop.

If only Taylor’s film on the whole had been closer in purpose to the elements at which the abovementioned scenes succeed. Instead, “Black and Blue” registers as a standard-issue cop thriller with merely fleeting insights on the racial and social issues it aims to dismantle, while often being overwhelmed by Geoff Zanelli’s redundantly severe score that competes with the onscreen action. Despite the efforts of a compulsively watchable Harris, Taylor’s fast-paced mode misses out on a real opportunity amid all the noise, one that could have touched upon a nerve in a deeper and more urgent sense.