Monsters vs Aliens contains an interesting mix of contradictions. It’s shot and animated using up-to-the-minute technology but in the service of a decidedly old-fashioned story; it’s steeped in the 1950s B-movie tradition, but its premise is decidedly feminist. Even the use of 3-D technology is complex, simultaneously reaching back to the gimmicky 3-D films of the 50s while hoping to pull modern audiences away from their computer screens and back into theaters.
Those juxtapositions are the most challenging and interesting thing about the film, which is mostly a paint-by-numbers action yukfest. This level of harmless fun and limited ambition is par for the course for a non-Pixar animated film these days (Kung-Fu Panda was a recent exception).