Giant ants invade the New Mexico desert, an aggressive mutation spawned by the frequent nuclear tests of a decade prior. Our heroes (a ragtag group of trigger-happy policemen, bemused FBI agents and scolding, voice-of-reason scientists) manage to annihilate the bugs' first nest, but several escapees slip the net, take flight and hole up in the sewers beneath Los Angeles.

For all the inherent silliness of a movie about nine-foot insects, plus the technical limitations of the period, this actually isn't half bad. Late budget cuts created a few hurdles, including a shift from color to greyscale and a reduced number of prop ants, but the plot barrels along undeterred and a few wily camera tricks sufficiently cover for the relatively small number of monsters. I expected those creepy-crawlies to hold off until the third act, padding the run time (as usual) with a glut of dull talking heads, but instead we get elbows deep in enormous larvae and firebomb a series of human-sized tunnels within the first half-hour.

It's a peak example of the mid-50s creature feature, complete with an oversized premise, comical special effects and heavy-handed morals, but also a well-constructed film that speeds along at a breakneck pace and always follows through on its promises. You want big, hairy, irradiated ants versus army men with bazookas and flame throwers? You got it.