Roger Corman's Attack of the Crab Monsters is just one of many cheapo monster movies from the 50s to blame nuclear fallout for messing up nature, and features lots of the elements one might quite rightly expect from the genre—a team of brave US scientists (including the obligatory pretty female doctor), wooden acting, unconvincing locations, and crummy effects. However, it also manages to present a few unique ideas that elevate it above many of the standard 'mutated monster on the loose' creature features of the era.
The critters that grow to massive proportions in this film are land crabs that have been exposed to radiation from A-bomb tests, but rather than simply being scaled-up versions of regular crustaceans, these guys possess an atomic structure consisting of liquid in a permanent form, making them extremely hard to destroy; they also have the ability to assimilate their victims, absorb their knowledge, and lure further victims to their death by talking to them telepathically. Pretty far-fetched I know, but very creepy, the crabs eerie, echoey, disembodied voices being surprisingly effective.
Of course, given the movie's low low budget, the monsters themselves are pretty rubbish—awkwardly moving lumps of papier-mâché with gangly legs dangling uncontrollably, coat-hanger antennae, and massive human-like eyes that look really daft—but I wouldn't have it any other way: a badly designed, poorly constructed monster is half the charm of a B-movie like this.
6.5 out of 10, rounded up to 7 for a couple of surprisingly nasty moments (a decapitated body and a severed hand—in black and white, but still pretty gruesome) and the somewhat unnecessary but enjoyable underwater swim by Pamela Duncan.
