G.I. Joe: Retaliation: Just a bloated version of its own bang-bang trailer What a blast G.I. Joe: Retaliation is! And then another blast, and another, in a series of concussive jolts that shred any conventional sense of story as thoroughly as anything since the last Michael Bay film. This sequel/reboot to 2009"s G.I. Joe: The Rise of Cobra, based on the Hasbro plastic soldiers and the spinoff comic-book series, feels like a five-year-old with a megaphone, excitedly yelling about his latest bulldozer-soldier-dinosaur smash-kill-squash-everything game. G.I. Joe: Retaliation is really a bloated version of its trailer, featuring a series of set-piece action sequences with bulging muscles and weapons, from nunchucks to nuclear warheads. Director Jon M. Chu (who directed the Step Up dance movies and Justin Bieber's concert film) introduces characters and exposition briskly, between the action montages of slice-and-dice editing, whip pan and slow-motion camera work. All of this shows a merry disregard for the conventions of space and time, as we leap about from Korea to Pakistan, Washington, Nepal, Tokyo and Germany, most of which look like warehouse sets, bolstered by CGI backdrops. And all, of course, in 3-D, so we can immerse ourselves in the ammo blasts. Most of the fights are between the good guys (a commando group called G.I. Joes) and the bad guys (Cobra), and everyone has special skills just shy of Avengers-level superhero abilities. One of Cobra's big assets is that they have a fake president of the United States named Zartan (Jonathan Pryce), who has the real president (Jonathan Pryce again) held captive and tortured by various means, including barbaric puns. "They call it a water board - but I'm never bored." The evil fake president causes the G.I. Joes to get ambushed and framed for the assassination of the Pakistani president. Among the survivors are Duke (Channing Tatum), who has a sensitive pout, Roadblock (Duane Johnson), who has big biceps and an ironic right eyebrow, and Lady Jaye (Adrianne Palicki), who has superior analytic skills and, to distract the enemies, breasts. Finally, the Joes recruit gun-nut General Joe Colton (Bruce Willis in a cameo), who provides wisecracks and more bald badness. On the evil side, things are even more chaotic. Sleek martial-arts whiz Storm Shadow (Lee Byung-hun) and a Southern tough guy named Firefly (Ray Stevenson), who throws mechanical exploding firelies, rescue the growly voiced Cobra Commander in a Darth Vader mask (Luke Bracey). Then Storm Shadow heads home to the Himalayas to recover from his wounds and is kidnapped by a team of ninjas who take him to Tokyo in a body bag. Afterwards, Storm Shadow and a female character in a skin-tight body suit, Jinx (Elodie Yung), decide to join the G.I. Joes to defeat the fake president, Zartan. In the end, all the leaders of the free world are at a summit where they have video-game controllers to blow up the world in the guise of destroying their nuclear arsenals, and Zartan is playing Angry Birds on his phone and mocking them. Unfortunately, London gets destroyed (poop happens, as they say in the military), though otherwise things end well, with lots of awards and salutes all around and enough narrative loose ends for another sequel or 12. But now it's time to stop because Daddy has a major 3-D headache, and I think it's time to tuck the G.I. Joes back in their bunker and think hard about what happens when everyone gets too excited. In the morning, the G.I. Joes and Cobra can tell London they're very sorry for what they did, even if I'm not quite sure what it was.