When I was nine years old and saw this child's out-of-her-mind-terrified reaction upon regaining her memory of the horror she'd witnessed, I knew I was not in for just any run-of-the-mill 1950's giant monster yarn. And I was right.
The Medford's both know their shit and all of the mounting evidence clearly shakes them to the core, but they refuse to tell either the FBI or the police what they suspect until they are absolutely positive. Then, while searching the desert where the earlier incidents occurred, the investigators run face-first into an ant roughly the size of a city transit bus and barely escape with their lives after dispatching it with firearms. But that was just one lone specimen, and as everyone knows, ants are hive insects...
A "HOLY MOTHERFUCKING SHIT!!!" moment if ever there was one.
A descent into an atomic age hell.
The entire world in danger of getting its collective asshole eaten out by millions of giant mutant Formicidae? It just doesn't get more serious than that, folks, and the film knows it in no uncertain terms. THEM! unfolds like a scientific procedural, which it is, and we are engrossed every step of the way, making shocking discoveries along with the non-scientists. I first saw this film when I was nine years old and, speaking as the son of a veteran biology teacher, I went into it knowing nothing as to what it was about, but I knew a lot about ants, so when formic acid came up as part of the mystery, my mind did the math and I was gobsmacked by the horror of what an invasion of gigantic, hungry, savage, and reproductively viable examples of those creatures would mean. The script treats the viewer as intelligent, and at no point do any of the characters do anything stupid when facing such a threat to the entire world, which absolutely endeared me to the film as a kid who hated being talked down to.
Seriously. Just stop and think about this fate for a moment. Yeah, HELL NAW.
And I would be remiss if I did not single out Joan Weldon's groundbreaking portrayal of Dr. Pat Medford for praise. In an era marked by its rampant phallocratic/chauvinistic/misogynistic leanings, Pat's take-no-shit, all-business attitude when dealing with her job as a scientific expert and handling her masculine "superiors" was quite refreshing to see and admirable on the part of the filmmakers. It was quite clear that though attractive she may be, Pat's looks and gender had zero to do with her competence as a scientist or her steel-hard bravery when directly confronting the unthinkable once she got down to business. Sure, she screamed and nearly shat a Humvee when first encountering a shrieking giant ant, but who in their right mind wouldn't have, be they male or female? But once it was time to kick some scientific ass and save the world, Pat proved logical, methodical, and possessed of nerves of steel. Since I was a child, she's been among my top-tier roster of sci-fi/horror movie heroes, and she has my utmost respect. It makes me squirm with geekish delight when I imagine what she would have made of the events at the terraforming colony on LV-426 and how she would have teemed with Ellen Ripley to hand out flamethrower ass-kickings to the legion of xenomorphs.
Dr. Pat Medford (Joan Weldon): taker of zero shit and one of the saviors of the world.
Poster from the original theatrical release.