Grade: C

It’s certainly well-meaning and handsomely presented (in 3D computer-generated animation, with a starry voice cast). But in the end, for all its good intentions “Battle for Terra” is a pretty pallid, pedestrian affair, a very mild outer-space adventure with an ecological message that, in the age of Pixar, is unlikely to keep kids, or their parents, rooted to their seats for 85 minutes.

The picture is set on a planet inhabited by a happy, peace-loving race of what look like talking tadpoles with oval faces reminiscent of the aliens from “Close Encounters.” The civilization is threatened by an armada of spaceships whose inhabitants—refugees from another galaxy who’ve destroyed their own planet through their misjudged policies—are looking for a new home that can sustain them. The linchpin of the story is Mala (voiced by Evan Rachel Wood), a sweet but adventurous young tadpole whose father (Dennis Quaid) is kidnapped by the advance scouts of a potential invasion force. She wants to rescue him, but she also shelters Jim (Luke Wilson), an injured “enemy” pilot, by keeping him from capture by her fellow tadpoles.

It turns out, of course, that the armada is from earth, which was poisoned by the humans it’s carrying, and the refugees are divided about how to deal with this new planet, called Terra, which can be transformed into an environment that will support them through technology—but only in a way that means it will cease to be habitable for its current inhabitants. The “civilian” leadership of the armada wants to seek a peaceful accommodation with the locals, but the military chieftain (Brian Cox) takes advantage of the fact that the ships are about to run out of air to stage a coup and order what he calls Terraformation, which will mean the death of Mala’s race.

By this time, however, she and Jim have joined forces, and what results is a big air battle—shades of “Star Wars”—in which a Terran fleet tries to destroy the Death Star (sorry, Terraforming Machine) deployed by the general while the invading airships work to defend it. This being a family film with a positive slant, you can be sure the carnage will be minimal—by which we mean, lots of explosions but not much explicit loss of life—and that ultimately the Rodney King question will be answered, species-wise, in the affirmative.

So in the end “Battle for Terra” tries to be a warning about the danger we pose to our planet while providing a comforting outcome about humankind’s ability to reject violence in favor of cooperation and mutual respect with other beings. That’s very nice, of course. It would be nicer, though, if the script that delivered the message were less tepid and obvious, and the characters more vibrant. Wilson’s Jim is probably the weakest link (a more stalwart-sounding voice might have helped), but even Wood’s Mala comes across as fairly anonymous, and Cox overplays the nasty general. The animation is sometimes quite impressive visually, even in the 2D format, but as usual the humans seem like stiff plastic figures (the odd but attractive Terrans come off better). But as so often nowadays in terms of CGI animated pictures, it’s a case of a mediocre present in a pretty package.

“Battle for Terra” is well-intentioned, and a great deal of effort has obviously gone into putting in onto the screen. A pity it turns out to be so distressingly limp, though visually impressive.