In theaters

THE MATRIX REVOLUTIONS, written and directed by Larry and Andy Wachowski, 129 minutes, rated R.

To enjoy “The Matrix Revolutions,” it’s probably best to enter it with lowered expectations.

Written and directed by Larry and Andy Wachowski, this ambiguous, bloated, occasionally stunning and technically magnificent concluding chapter in the “Matrix” franchise offers no primer to where it has gone before. If you do decide to see it, viewing the two previous films are not only required, but also required recently.

Otherwise, you’re almost certain to be lost.

Picking up where last May’s “The Matrix Reloaded” left off, “Revolutions” opens with a comatose Neo (Keanu Reeves) hovering somewhere between this world and the machine world. It’s a space the Wachowskis envision as a gleaming subway station called Mobil – an anagram for limbo – with the evil, disheveled Trainman (Bruce Spence) refusing to let him go home.

It’s up to Trinity (Carrie-Anne Moss), Morpheus (Laurence Fishburne), and Seraph (Collin Chou) to find a way for him to get back, which involves storming an underground, fetish-friendly discotheque called Club Hell. There, the trio eventually confronts the wonderfully Eurotrashy Merovingian (Lambert Wilson) and his busty sidekick, Persephone (Monica Belucci).

Among the more interesting characters in the series, these two mincing archetypes appear only fleetingly, which is a disappointment since they add necessary life and fire to a movie whose tone has become a dirge.

Still, they’re crucial to the plot. Through them, Neo is eventually released and, after a mostly uninvolving first third that features several chatty side trips with the smoky, all-knowing Oracle (Mary Alice, replacing the late Gloria Foster), the real action begins with the mesmerizing liberation of Zion.

Here, the movie lets loose. In a fantastic special effects extravaganza that dazzles, millions of spermlike Sentinels literally put the screws to the massive sphere harboring Zion’s remaining human inhabitants.

The scene erupts rather nicely, with Zion’s humans suiting up as towering robots to quash the crushing invasion. Meanwhile, Neo, more Christlike than ever, is preparing for his final showdown with Agent Smith (Hugo Weaving).

Whether you find the movie worthwhile will depend on what you’re seeking.

What began in 1999’s “The Matrix” as a reasonably fresh, interesting collision of New Age ideas and religious retro-talk in a computer-fried world, has become a technically masterful yet thematically stunted sci-fi blockbuster whose alleged depth has turned out to be mostly smoke and mirrors backed by cliches.

Having run out of steam, the Wachowskis resort to that current bane of the movie industry – film piracy. They try to bolster “Revolutions” by pilfering liberally from a wealth of other sources – “Alien,” “Aliens,” “Star Wars,” “Superman II,” “The Wizard of Oz,” “The Thing,” “Mad Max,” “War of the Worlds,” “Frankenstein,” “Robocop” and “Tron,” to name a few. Doing so causes the movie to lose its identity along the way.

The best, most memorable performances come from the supporting cast – Jada Pinkett-Smith as the fiery Niobe, Harry Lennix as Commander Lock, and Harold Perrineua as Link. With them, there’s at least a measure of passion involved, a welcomed reprieve from the glum, tight-lipped solemnity offered by Neo, Morpheus and Trinity.

As you’d expect, “Revolutions” doesn’t end with a gag reel, but is that such a bad idea for the DVD release? At the very least, it would offer some insight into the production, which hopefully wasn’t nearly as humorless as it appears to have been.

Grade: B-

On video and DVD

TERMINATOR 3: RISE OF THE MACHINES, directed by Jonathan Mostow, written by John Brancato, Michael Ferris and Tedi Sarafian, 109 minutes, rated R.

Unforgiving in its leanness and its huge action pieces, some of which literally destroy entire city blocks, “Terminator 3: Rise of the Machines” is pure meat-and-potatoes fun. It finds the newly elected governor of California, Arnold Schwarzenegger, back in fine form in what’s arguably the most famous role of his career.

This time out, the world’s future hangs in the balance by yet another cyborg, a leather-clad, impossibly curvaceous Terminatrix (Kristanna Loken) downloaded from the future to murder John Connor (Nick Stahl), the much-maligned savior of the world who has been hunted down by machines since before he was born.

To get to Connor, this potent, pixelated pixie – T-X, as she’s formally known – will have to go through Arnold’s T-1, an “obsolete design” who finds himself protecting not only Connor, but also Kate Brewster (Claire Danes), a shrill veterinarian connected to the action in a haze of coincidences.

What ensues isn’t as gripping as it was in James Cameron’s hands – director Jonathan Mostow isn’t as deft in wedding his action to the film’s emotional undercurrent, and you do feel the loss of Linda Hamilton’s Sarah Connor, who was unfortunately written out of the script. Still, the movie is better than you might expect.

Mostow and his writers, John Brancato, Michael Ferris and Tedi Sarafian, respect what came before it. They unleash the action at a blistering pace, Arnold rips off a few noteworthy one-liners, and the film ends with the prospect of another movie.

Grade: B

Christopher Smith is the Bangor Daily News film critic. His reviews appear Mondays and Fridays in Style, Thursdays at 5:30 p.m. on WLBZ 2 and WCSH 6, and are archived on RottenTomatoes.com. He can be reached at BDNFilm1@aol.com.