After three films, "Transformers: Age of Extinction" partially reboots the movie series. Shia LaBeouf is out, Mark Wahlberg is in, and Michael Bay sticks to what he does best by providing plenty of giant robots and big explosions. As with all of Bay's films, "Age of Extinction" is an entertaining popcorn flick, but it falls apart if you look too closely.

Five years have passed since the giant Transformers battle destroyed much of Chicago in "Dark of the Moon." After the civilian casualties from that skirmish, the tide has turned, and the Autobots are considered dangerous alien beings rather than benevolent allies. A CIA task force led by Harold Attinger (Kelsey Grammer) is on a mission to destroy all Transformers, whether Autobot or Decepticon. Propaganda posters with "Remember Chicago" are posted everywhere, and people are encouraged to report Transformer sightings or be arrested for harboring a fugitive.

Meanwhile, in rural Texas, Cade Yeager (Wahlberg) is an inventor-slash-repairman who is having trouble making ends meet. As a single father, he's overly protective of his teenage daughter, Tessa (Nicola Peltz). He uncovers a heavily damaged semi-truck while shopping for spare parts, and he buys it, thinking he can strip it and sell the parts. Of course, the semi turns out to be Optimus Prime (Peter Cullen), and Cade, who can't build any robots that work properly, somehow manages to repair Optimus.

The task force quickly descends on them, and as Optimus lays down cover fire, Cade, his daughter, and his business partner Lucas (T. J. Miller) flee with the help of Tessa's boyfriend, Shane (Jack Reynor). Cade discovers that the operatives are working with Kinetic Solutions Incorporated (KSI), a Chicago company led by visionary Joshua Joyce (Stanley Tucci), who's eerily reminiscent of Steve Jobs. Cade is determined to set things right; to do so, he must take on KSI and the American government. No big deal, right?

Although nobody watches a "Transformers" movie for the story, there are some pretty glaring plot holes in "Age of Extinction." In the initial shots, Chicago has been decimated. In the middle of the film, the battle returns to Chicago — easily identified by "The Bean" — everything has been miraculously rebuilt in five years' time. Yes, Attinger is running a very public CIA operation on domestic soil with Presidential knowledge and approval even though it's expressly forbidden.

Since it's a Bay film, there are plenty of explosions, and the magnitude of destruction almost puts "The Avengers" to shame. The action sequences are long but too frenetic, leading viewers to sometimes puzzle over who's fighting who. The visual effects don't disappoint, and the 3-D is pretty good. Before the movie began, there was a short film about how Bay used IMAX 3-D cameras to create impressive vistas, but they weren't close to the caliber of the scenes in "Mission Impossible: Ghost Protocol." Perhaps the 3-D surcharge would be justified if you want to splurge, but you can safely skip the IMAX on this one.

Clocking in at almost three hours, "Age of Extinction" is indulgently long. There are his trademark scenes where characters look off into the sunrise/afternoon sky/sunset and look contemplative while dramatic music plays in the background. The Cade-Tessa-Shane scenario brings to mind the similar situation from "Armageddon," which was also a Bay film, essentially making this film an homage to himself. There were a few stereotypes that made me a little uncomfortable, but it's a summer action film, so I should stop overthinking it.

Wahlberg, while an improvement upon the prior protagonist in every way, just isn't believable as a cerebral inventor — even with his glasses on. The only thing I believe he can invent is how to get such huge biceps on a diet of burgers and beer. Aside from fulfilling the damsel in distress requirement, the Tessa character could have been removed from the script, and nothing would change because she doesn't contribute or do anything.

I'm unsure if this was the fault of the film or the screening location, but sound-wise, the voices were sometimes muddled and difficult to understand.  The voices of Cullen and John Goodman (as Hound) come through loud and clear, but the rest of the cast was hit-and-miss.  Hound has some great one-liners, so Goodman was an enjoyable highlight.  Although Cade and Tessa have lived in Texas their entire lives, they don't have a Southern drawl.  Tessa's boyfriend, Shane, plays an Irish rally car driver, but his accent comes and goes, and he sometimes sounds Australian.

When Cade is shopping for spare parts, the ornery owner bemoans the current state of movies and their numerous sequels.  One can only hope that it's tongue-in-cheek.

"Transformers: Age of Extinction" is a good reboot and a great summer action film, but most importantly, there are Dinobots and Galvatron.  Sure, it has its share of problems, but when everything's exploding as giant robots battle it out and you shovel popcorn into your face, you won't notice or care.

Score: 7.0/10

"Transformers: Age of Extinction" is rated PG-13 and has a running time of 2 hours and 45 minutes. It's showing in 2-D, 3-D and IMAX 3-D.