State trooper Sgt. Ben Peterson (a young James Whitmore, who would later play Brooks the librarian in The Shawshank Redemption) and his partner pick up a 7-year-old girl walking in the desert near Alamogordo, New Mexico. She appears to be in a state of shock and won’t talk, while the trailer she was staying in is found to be destroyed, without a trace of her family.

The cops find a nearby general store in the same disarray, its owner dead in the cellar. Ben leaves his partner behind as he goes for help. A strange whistling noise lures the cop outside, where he gets off a few shots before letting out a scream.

The missing family turns out to include a vacationing G-man, so the FBI sends Agent Graham (James Arness) to help investigate. A strange footprint attracts a pair of entomologists (Edmund Gwenn, Joan Weldon) from the Department of Agriculture, who arrive with a unique theory for the case. The appearance of an 8-foot ant as they search the crime scene substantiates that atomic testing has super-sized a colony of ants.

Our heroes locate the nest and drop cyanide gas inside. Going underground, they discover that two queen ants have already hatched and apparently flown away. The government keeps news of the creatures quiet, while Ben and Agent Graham track the queen ants to Los Angeles, where they have infested the sewer system setting up a new nest.

Directed by Gordon Douglas from a screenplay by Ted Sherdeman and Russell Hughes and story by George Worthing Yates, Them! was originally to be shot in Technicolor and 3-D, but these were scrapped before filming when Warner Bros. deemed them too expensive. The picture ended up being their biggest moneymaker of the year, and is widely considered one of the four-star sci-fi movies of the 1950s.

What I love about the flick is that it unfolds like a murder mystery, not a sci-fi movie. If you didn’t know what “them!” is, you wouldn’t find out until almost 30 minutes into the film. Yes, once we do see the giant ants, the lack of technical innovation is obvious, but the less we see of them, the more intense the movie is. I can recall seeing this at the River Oaks Theater in Houston as a kid, and the shadow of an ant on the sewer wall as it creeps toward Whitmore freaked me out.

Them! is well cast, from Whitmore’s capable Officer Friendly, to Arness’ doofus G-man, down to the catatonic little girl who shrieks out the film’s title. Nobody camps it up here. Fans of nostalgia will notice appearances by Leonard Nimoy as an Air Force sergeant, and Fess Parker as a manic pilot. Legend has it that Walt Disney watched the movie to consider James Arness for the role of Davy Crockett, but was so impressed with Fess Parker’s portrayal as a colorful yahoo that he got the job instead.

Lot director Gordon Douglas did a sharp job on the film, making terrific use of the spooky New Mexico desert. The script is equally taut, with no backstory, no romantic liaison with the dame scientist. It’s all about people saving the world from giant bugs.

The music and production value are heads and shoulders above any of the sci-fi monster movies that would follow. James Cameron’s fingerprints are all over this, with the catatonic little girl, torching of an egg chamber and subterranean battles with bugs versus the military all appearing here before they would in Aliens. If your kids are still too young for a sci-fi thriller that intense, but want to see giant bugs run amok, this classic is highly recommended.