An efficient, if decidedly derivative, space-set monster movie in the "Alien" vein, 2000's "Pitch Black" proved a small sleeper success, just about doubling its no-frills $21-million budget and creating a star out of Vin Diesel (who would go on to make "The Fast and the Furious" the following year). In a total 180-degree reversal, Diesel's cache and the R-rated first pic's rising cult status helped to put mega, $100-million-budgeted "The Chronicles of Riddick" on the fast track. Downgraded to a dishonest PG-13 rating to compensate for the lofty costs, this tonally very different continuation traded its predecessor's horror roots for a futuristic sci-fi/action angle. The movie looked every bit as expensive as it was, but it was a complete and utter mess all the same—overblown, lacking in emotion and characterization, unbearably dull, and nearly impenetrable. Not surprisingly, "The Chronicles of Riddick" crashed and burned at the summer 2004 box office, signaling the non-triumphant ending to a disparate pair of films. Nine years later, Diesel has seen a resurgence of his star thanks in no small part to a little car-centric franchise that perplexingly keeps making more money with each new sequel. Pared down and aiming to recapture the darker, grittier feel of "Pitch Black," third-parter "Riddick" goes easy on the convoluted plot of the second film, but cannot seem to decide what it wants to be about. So halfhearted as a creature feature that said monsters are an afterthought, "Riddick" tests one's patience while basically boiling down to a lot of squabbling between characters not worth caring about.

Tired of his mundane royal existence as the new Lord Marshal of the Necromongers, Richard B. Riddick (Vin Diesel) gives up his throne and decides to head back to his home planet of Furya. Instead, he is betrayed and dropped perilously onto the foreign "Not Furya," left to fend for himself against any number of alien species while nursing a broken leg. With a bounty placed on his head, Riddick's desolation comes to an end with the arrival of a group of mercenaries led by the highfalutin Santana (Jordi Mollà), out to find and kill Riddick. Not far behind them is another ship captained by Boss Johns (Matt Nable). They want to find Riddick, too, but their interests, it turns out, are in keeping him alive. As an ill-boding storm moves in, so do vicious alien predators that have them surrounded.

"Riddick" kicks off with a promising first act, scant in dialogue and relying on enticing visual storytelling from returning writer-director David Twohy (2009's "A Perfect Getaway"). With Riddick left physically hurt and stranded, he must think quick to reset his broken bone and evade a host of deadly species out to rip him apart. Taming a dingo pup as his sidekick, he seems to be one step ahead of his feral pursuers, yet nonetheless hopelessly alone and with no way of getting off this planet. Twohy and co-scribes Oliver Butcher and Stephen Cornwell (2011's "Unknown") are initially on the right track, wise to focus on antihero Riddick as the CGI-enchanced special effects help to bring flavor to a dank new world overrun by animals decidedly not of planet Earth. Once the two warring merc clans show up, interest gradually deflates. With the different imaginatively conceived alien species put on the back-burner, the setting moves primarily indoors as Santana and Johns bicker and then bicker some more over their intentions in capturing Riddick. As for the title character, he lays in wait for such a long time it wouldn't be out of the question for some viewers to forget he's in the film. By the time the otherworldly villains pop up, seen rising out of the moist ground as rain pours on top of them, Twohy can barely be bothered. There is no detectable apprehension worked up because they are constantly playing second fiddle to rail-thin characters passive-aggressively arguing while spouting out needless exposition.

Vin Diesel (2013's "Fast & Furious 6") has starred as convicted murderer, convict, and unlikely hero Riddick in three movies now, and he remains just as much an enigma as he was when he originally essayed the role thirteen years ago. This isn't Diesel's fault—he commands attention in the early scenes where he is the only live-action guy onscreen—but it is quite telling that Twohy has failed to properly explore who he is, and why, over the span of a trio of movies and six collective hours. The rest of the actors are dutiful but lackluster, with Jordi Mollà (2010's "Knight and Day") oozing with smarminess as Santana and Katee Sackhoff (2002's "Halloween: Resurrection") attempting to give color to a weakly developed part playing Johns' tough, acid-tongued right-hand gal Dahl. The supporting players are deciphered by what they look like since they're all otherwise interchangeable.

"Riddick" is a slight improvement over "The Chronicles of Riddick," but not by enough to make a difference. Because the opening fifteen minutes are apt to build the viewer's hopes up, it comes as quite a defeat when it's all downhill from there. Director David Twohy has no idea what kind of a film he wants to make, settling for an uneasy amalgamation between the first two without committing to either side. As science fiction, it is pedestrian and thematically empty, its suggestion that the people on hand are just as dangerous as the monsters outside striking a particularly trite note. As an action movie, it's way too talky. And, as a horror picture, there isn't a raised pulse to be had past that first fleeting segment with Riddick going mano-a-mano with the wild beasts nipping at his heals. There is a grisly bit involving bear traps, but otherwise there isn't much to notably call attention to. "Riddick" is a blah effort, sinking into mediocrity when all involved—the writers, the director, the actors, the behind-the-scenes technical artists—are capable of so much more. Based on the wearisome continued evidence, perhaps Riddick would have been wise to hang up his protective sunglasses for good following "Pitch Black."