The title sums up this film, really. GI Joe: Retaliation is the epitome of action films. People shoot other people, explosions go off, Aerosmith plays in the background of every other scene, and it has the emotional impact of a damp sponge slapping against gravel. I could watch it again, because I like ninjas and it has quite a few of those.
Dwayne Johnson is good, as the rock-solid (pun acknowledged but not intended) hero of the film, who dutifully fires all the big guns and looks suitably unimpressed by other characters' shenanigans. I believed him, because that's what Johnson's been doing 1996, and he has the charisma to pull it off. He's like a concrete puppy.
Adrianne Palicki and DJ Cotrona are okay as his commando sidekicks. Like most of the characters in this film, they lack any real personality to connect with. Palicki's character has daddy issues, which I would sympathize with had it not been done to death in every possible medium of entertainment already, which affect her for all of one scene.
Cotrona's jumps on people from behind and looks uncertain occasionally, possibly wondering why he isn't dressed as a ninja.
I can't think of much to say about the rest. Bruce Willis doesn't actually do anything, besides showing people around a house and looking smug, and the villains are instantly forgettable. Firefly could have been interesting, given a bigger role. Storm Shadow goes through the motions.
And as for Cobra Commander...well, the person behind that helmet could be anyone. I forget why anyone bothered defrosting him in the first place. The biggest moment of villainy he gets is spoiled by the fact that no one really cares. Apparently.
The most villainous man in the movie, by the way, doesn't even get a name. I won't spoil him for you, but the fact I remember him is a bit of a sticking point. GI Joe: Retaliation is, unfortunately, just what you expect it to be- yet another action movie. With ninjas.