Villain(s)  Giant ants

Actor(s):  James Whitmore, Edmund Gwenn, Joan Weldon, James Arness

Brief Description  Them! (1954) is a landmark Warner Bros. science fiction monster film directed by Gordon Douglas that famously launched the "giant bug" cinematic craze of the Atomic Age. Grounded in Cold War anxieties and structured primarily as a tense law-enforcement procedural, it follows the discovery and military containment of nine-foot-tall, radioactive killer ants spawned by early nuclear testing.

Plot:
New Mexico State Police Sergeant Ben Peterson and his partner find a catatonic, shocked little girl wandering alone in the desert. They soon discover her family's vacation trailer completely torn apart from the outside, with all money left untouched but a strange footprint nearby. A local store owner is found dead and mangled in a similar fashion, with a massive amount of formic acid present in his body. Fearing an unknown threat, the FBI sends agent Robert Graham, alongside Dr. Harold Medford and his daughter Dr. Patricia Medford—both entomologists from the Department of Agriculture. Dr. Medford snaps the little girl out of her catatonia by waving a vial of formic acid under her nose, causing her to scream, "Them! Them!" Soon after, the team is attacked in the desert by a 9-foot-tall mutated ant. They manage to kill it by destroying its antennae, which blinds its senses.

Dr. Medford reveals the creatures are genetic mutations caused by the first atomic bomb test in 1945. Using aerial sweeps, the military locates the primary desert colony. They bombard the nest with cyanide gas bombs and venture deep into the subterranean tunnels with flamethrowers. Though they destroy the colony, Patricia discovers an empty chamber: two newly hatched queen ants and their consorts have already flown away to establish new territories. The government imposes strict media censorship to prevent nationwide panic while tracking the missing queens. One queen nests inside a freighter ship at sea, which is quickly sunk by the Navy. The second queen infiltrates the massive, labyrinthine storm drain system beneath Los Angeles. The military locks down the city, trapping the queen and her newly hatched brood in the concrete spillways. In a fierce final battle, Sergeant Peterson sacrifices his life to save two young boys trapped in the tunnels before the remaining bugs are completely torched.

Unlike later B-movies that treated monsters campily, Them! treated its premise with serious, scientific matter-of-factness. It reflects deep post-WWII anxieties regarding the unknown ecological and genetic consequences of weaponized radiation. The movie is celebrated for its slow-burn pacing. It behaves like a detective noir police procedural for the first 30 minutes, delaying the visual reveal of the monsters to build suspense. Due to its immense influence on science fiction, the film was officially selected for preservation in the United States National Film Registry by the Library of Congress in 2017.