“We were a peaceful race of intelligent mechanical beings,” asserts Optimus Prime (voiced by Peter Cullen) at the start of Transformers: Dark of the Moon. And then they weren’t. Good thing the Autobots were rigged with awesome weapons when they were attacked by the Decepticons, another set of mechanical beings, apparently less peaceful. 

Their battle occasions some big-boomy revisionist history (see also: X-Men: First Class). Here, a crash landing on the moon by Optimus Prime’s mentor, Sentinel Prime (Leonard Nimoy) left behind a pile of scary technology, and also inspired John Kennedy to “choose to go to the moon” sooner than he planned, or so you hear from a very poorly digitized JFK. (Really, with all the millions spent on Transformers 3‘s legions of 3D robots and explosions, no one thought to clean up the faux Kennedy?) The pile also inspires an equally badly imitated Nixon to send Neil Armstrong and Buzz Aldrin (who actually makes an appearance in Transformers 3, the better to endorse this silliness) to the moon in 1969, at which point Nixon pronounces his own interest in “peace”: “As you talk to us from the Sea of Tranquility, it inspires us to redouble our efforts to bring peace and tranquility to Earth.”

Of course, the pursuit of peace per se wouldn’t make for much of a Michael Bay movie, and so the humans and the Autobots have this in common: they like to fight for peace. They’ll do it for freedom and justice and truth, too. But mostly they do it for peace.

This formulation provides the rationale for most everything that follows in Transformers 3. And it’s most plainly embodied, as before, in Sam Witwicky (Shia LaBeouf). At the moment he enters the picture, Sam is feeling less peaceful than anxious. Like so many recent college grads, he’s unable to find work, and so he complains loudly and acts out childishly with his new girlfriend, Carly (Rosie Huntington-Whiteley). (Her function here is summed up in her introduction: a jokey tracking shot of her barely covered bottom as she walks up a set of stairs to her man-boy’s bed; yes, she’s a Victoria’s Secret model and yes, she’s an egregiously unprepared actor.)

The film goes on to provide reasons for Sam’s obnoxiousness, including his forced disassociation from his best friends and fellow world-savers, the Autobots, and the relentlessly clueless Carly’s employment by superrich, insufferable car collector named Dylan (Patrick Dempsey). As Sam whines and harrumphs and tries to convince everyone who will listen that he’s saved the world—twice—but can’t get a job, Carly repeatedly forgives his tantrums, his glowers, even his downright meanness: “It’s hard for everybody to get a job!” she says brightly. 

Before you begin worrying that Transformers 3 is headed down a path of social or even political commentary, the camera is circling Carly’s lissom surface, emulating Dylan and Sam’s competing gazes. As you might guess, their competition has higher stakes than Carly (though, as a damsel in need of rescuing, she occasions a series of necessary plot points). The boys have different investments in this peace business, and so they choose up sides differently. While Dylan is briefly off-screen, Sam is briefly distracted by working for a company run by the odd Bruce Brazos (John Malkovich). Here—specifically, in the men’s room—he runs into a coworker named Wang (Ken Jeong), possessed of a transformers’ memo for Sam, and so disposed to pull down his pants and present one of the film’s juvenile “gay jokes.” (At least this third installment has lost the jive-talking robots of Revenge of the Fallen.)

Wang suffers a terrible fate for his trouble, but Sam finds himself reunited with Bumblebee, as well as disrespected by National Intelligence Director Mearing (Frances McDormand), currently in charge of the Autobots. You can understand Mearing’s misgivings when Sam arrives at the Autobots’ facility in DC with “world class hottie” girlfriend in tow (especially when said girlfriend essentially stomps her foot in defiance), but you also know that Sam’s got to get a piece of this action. And so Mearing is soon relegated to the part she must play, the nescient government official.

That is, Mearing’s own efforts to secure peace by means of “intelligence” are soon overwhelmed by the need for fighting. Enter the franchise veterans, Special Forces Army Ranger Lennox (Josh Duhamel), Air Force Master Ranger Epps (Tyrese Gibson), and former Sector Seven agent, now best-selling and self-promoting author, Seymour Simmons (John Turturro), who comes equipped with the film’s other “gay joke,” the splendid tech-assassin-assistant (Alan Tudyk). As the guys reunite with their Autobot buddies, they learn that the Decepticons—again led by Megatron (Hugo Weaving)—are gathering for a world takeover in Chicago. And with this realization, the movie’s point comes into sharp focus: they must destroy the city in order to save it.

This final section of the 154-minute sequel does, at least, deliver on the Bay brand’s much-ballyhooed special effects. Cars crash, bullets fly, missiles explode, buildings collapse, robots rip each other’s arms off and blow each other’s heads off. (The 3D here smartly showcases depth of field rather than projectiles coming out at you, and so these violent acts are technically accomplished.) The Rangers contribute some impressive paragliding in wing suits, as well as a frankly remarkable slide down a towering glass office building that’s broken in half.

Hectic and hyper, the sum of the action is again less than its many parts…. which only means the movie takes you where you expect to go. The primary humans and mechanical beings are occasionally set against nameless Chicago residents who scream and run and fall, so much collateral damage amid the overwhelming firepower. As the Autobots and the human soldiers insist on their worthy cause, people seem incidental. Remember, the buddies keep telling themselves, “We’re fighting for freedom.” And peace, don’t forget that part.