The story begins with Susan Murphy (Reese Witherspoon), whose should-be-glorious wedding day is ruined by a stray meteor that first causes her to glow green and then to grow 50 stories tall, something her self-absorbed TV weatherman fiancée (Paul Rudd) just can’t handle. No matter--she is quickly captured by the U.S. government and hauled off to a secret facility where the feds have been holding various monstrosities and science experiments gone wrong for decades. Once in her massive holding cell, Susan is introduced to the movie’s cast of friendly monsters, each of whom derives from a particular strain of old school Hollywood horror. From the “Underwater Monster Department” we get Missing Link (Will Arnett), a sensitive fishman who was unfrozen from the Arctic and spent his heyday terrorizing beachgoers ala The Creature From the Black Lagoon. From the “Science Gone Awry Department” we have both Insectosaurus, a grub that grew to 350 feet after being exposed to radiation, and B.O.B. (Seth Rogen), who was once a tomato before being injected with a ranch-flavored dessert topping, which somehow turned him into a sentient blue blob whose lack of a brain makes him blissfully unaware of just about everything. Finally, from the “Mad Scientist/Vincent Price Department” we have Dr. Cockroach, Ph.D. (Hugh Laurie), a brilliant scientist whose own experiment gone awry left him with a cockroach head.

The monsters in captivity are the pet project of the George C. Scottish-ish General W.R. Monger (Kiefer Sutherland), who quickly rechristens Susan “Ginormica” just in time to call her and her newfound monster friends into service protecting the Earth from a marauding five-eyed alien overlord named Gallaxhar (Rainn Wilson). Hence, that grabby title, which first pits the monsters against Gallaxhar’s massive robot and then against an army of Gallaxhar clones, which are just as self-centered as their originator but not quite as bright. This provides plenty of opportunity for mass chaos and comedic destruction, much of which involves San Francisco being torn to shreds in the wake of the full-on Godzilla-style smackdown between the robot and Insectosaurus.

In between scenes of mass destruction directors Rob Letterman (Shark Tale) and Conrad Vernon (Shrek 2), who are working from a script by committee, shell out the comedy with a similarly rapid-fire style, hurling sight gags and puns and throwaway one-liners as if they, too, are in 3-D. Some of it works quite well, particularly the Dr. Strangelove-inspired scenes in the war room where the U.S. President (Stephen Colbert) is in constant danger of starting nuclear war because the big red launch button looks exactly like the button that produces a cappuccino. The interactions among the monsters when they’re not battling aliens produce some amusing and even touching rhythms, most notably when Missing Link feels underutilized in favor of the enormous creatures around him. Hugh Laurie has a great deal of fun with Dr. Cockroach’s mad scientist cackle, but it’s Seth Rogen who truly nails his character, turning B.O.B. into a delightfully vacant softie who falls in love with a plate of lime Jell-O. It’s not quite enough to elevate Monsters vs. Aliens into much more than a high-concept cash-in on technological gimmickry that will be all the more obvious once it’s reduced to two dimensions on home video, but it’s close.

Copyright ©2009 James Kendrick

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All images copyright © DreamWorks SKG Animation