Monsters vs. Aliens parades and parodies a long line of sci-fi horror B-movie tropes and cliches. Much of the audience for this movie will have never seen any of the original creations being gently goofed on. That's okay, because as is true of many of the movies that come out of DreamWorks Animation (Kung Fu Panda), Monsters vs. Aliens is a freestanding parody, an amiable comedy-adventure that requires no previous knowledge of pop cinema's rich and ridiculous history to enjoy its good, gooey fun. (My astute, B-movie deprived six year old companion enjoyed it very much.) There's a supersized, superstrong, possibly 50-foot woman, a blob, a mad scientist/insect man (complete with skinny Vincent Price mustache), a creature who could be from the Black Lagoon, or some pond nearby, a giant insectoid thing that roars like Godzilla, and a bunch of trigger-happy military guys pointlessly shooting ineffectual bullets.
The gigantic woman is an unhappy bride-to-be named Susan (voiced by Reese Witherspoon), who is about to marry a self-absorbed cad named Derek Dietl (Paul Rudd) when a meteorite ruins her wedding day and causes her to grow to enormous proportions. She's quickly whisked away to a secret government facility where she meets her fellow monstrous inmates: B.O.B. the blue blob (Seth Rogen), a shiny, gelatinous, elastic, one-eyed glob of goo; Dr. Cockroach, PhD (Hugh Laurie), a formerly human, now cockroachian mad scientist; The Missing Link (Will Arnett), a macho, finny amphibian; and a cute, enormous, fuzzy bug known as Insectosaurus, who is the big-eyed anime progeny of Godzilla, Mothra and all those monsters who ate Tokyo. When a gigantic alien robot invades Earth, the government calls on its captive monsters to save the planet.
What follows is familiar, wacky, and good-natured, and turns a previous generation's paranoia about the impending nuclear apocalypse into a shiny-happy fable of goofy goodness versus goofy evil. Monsters vs. Aliens promotes the values of loyalty, friendship, individuality and iconoclasm (monster-style) over mindless conformity. But it does not eschew mindlessness altogether. B.O.B. the blob is the gooey, shimmery, brainless heart and soul of the movie, the nice guy who gets the girl (well, sort of). Rogen's stoner-dude delivery -- you can hear the smile in his raspy voice -- makes the guileless B.O.B. the poster boy for heart (metaphorically speaking) without smart, which, in the sci-fi/robot/alien menace/war of the worlds/the end is nigh context, is always a safer bet than smart without heart.
Employing the relatively new and newfangled Real 3-D technology (which is immeasurably superior to the oldfangled 3-D), plus, in some locations, IMAX, Monsters vs. Aliens ups the ante on animation and visual spectacle. The 3-D really gives the animation visual depth and pop, making everything look bigger, shinier, blobbier, and richer. Because relatively few locations have 3-D screens yet (around here you'll have to trek to Albany or Poughkeepsie), the animation has to work on a "flat" screen too, so for the most part the gimmicky "thing zooming towards you" effects are minimized in favor of more subtle 3-D. Subtle, but definitely noticeable.
If the animation is crystal-clear and visually memorable, the movie's plot and gags stand out somewhat less, but Monsters vs. Aliens maintains a consistently slapsticky affability, with a decent share of laugh-out-loud moments and enough zippy action to ensure that a good time is had by all.