Planet 51

As the umpteenth computer-animated film released this year, “Planet 51” must contend with an over-saturated marketplace. That’s one strike. The second strike is that it’s not any good.

Written by “Shrek” veteran Joe Stillman and directed by a trio of Spanish newcomers, it’s set on an alien planet that resembles small-town America in the 1950s except that the people are green and rubbery. One of these alien teenagers, an amateur astronomer named Lem (voice of Justin Long), is in love with the girl next door, Neera (Jessica Biel) — though it’s a little weird that I’m even mentioning it, since the movie itself seems to lose interest in this subplot very quickly.

The important thing is that a spacecraft arrives one day in Lem’s neighborhood, and out of it comes an Earthling named Capt. Charles T. Baker (Dwayne Johnson), a preening, narcissistic NASA astronaut who is alarmed to find that there are life forms on this planet. (I assume it’s called “Planet 51” among Earth’s astronomers; no one in the film ever says it.) The life forms are pretty alarmed, too. They’d calculated the size of the galaxy in hundreds of miles, not billions, and had no idea there were pink-skinned aliens on a place called “Earth.”

Well, except for the leaders. Turns out NASA sent a rover to this planet some years earlier to gather intel, and it’s been hidden away in the local government’s equivalent of Area 51 ever since. Baker has to find it — it’s a robot that acts like a dog, and they call it Rover, and it looks a lot like WALL-E — and take it back to his ship, which is orbiting the planet. Trouble is, he can’t get back to his spacecraft to leave because the local military is monitoring it. I guess there is a reason why he can’t just present himself and say, “I come in peace; I mean you no harm; I just want to leave again” — but if there is, the movie does not explain it in reasonable terms.

Whatever the reason, Baker has to hide, and Lem decides to help him do it. The idea is that it’s just like those “visitors from Mars” B-movies, except reversed: The HUMAN is the alien! Get it?? Lem’s doofus friend, Skiff (Seann William Scott), who espouses all the conspiracy theories about aliens (species on other planets have those too, I guess), gives Lem a cork to put in his butt to prevent alien probes. I’m serious. He really does that. Somehow the word “butt” is avoided, but you get the idea. Later, some of the local kids accidentally see Baker naked, from the front, and one of them says, “That’s a funny place for an antenna.” That’s a fine joke, sure, but in a children’s cartoon? Tsk tsk, movie. TSK TSK.

The story is weak and uninspired. In addition to the lack of clarity about why Baker has to hide, there’s also the matter of his personality. He’s terrified of the aliens one minute, bossing them around smugly the next. There’s nothing real about him; he changes depending on the needs of the story. It’s also never clear why the local scientist (John Cleese) and military commander (Gary Oldman) lie about everything. And what about that girl-next-door thing? Who cares? Why include that obligatory romance if you’re not going to do anything with it?

Unfortunately, while the film is jolly and colorful, it’s also almost entirely laugh-free. This is strictly second-rate material, ignorable in a normal year but even more so when other, better animated entertainment is available.

D+ (1 hr., 31 min.; PG, a couple suggestive jokes, mild sci-fi violence.)