Phase IV

Phase IV would seem, on the surface, to resemble many of the other "Man Vs. Bugs" films that came out during the Seventies (like The Swarm and Kingdom of the Spiders). Phase IV, however, is a bit more cerebral than its brethren; the conflict with the ants in this movie more resembles a game of chess than it does an action-packed physical battle. It was the first and only feature-length film made by Saul Bass, who is better known for his innovative, animated opening title sequences for various classic movies, like Alfred Hitchcock's Psycho and Vertigo.

The film opens with the Earth undergoing the effects of a strange and rare cosmic alignment. Scientists aren't sure what effects, if any, the alignment has had on the planet and are quick to write it off. One scientist, however, notices some strange behavior beginning to occur amongst Earth's ant populations--they're becoming more intelligent and aggressive. They've begun attacking larger insects and animal species that are threatening them. Then the ants decide to take it a step further and attack a human community, destroying its houses and driving out its residents. (Mind you, the ants are still the same size as they were pre-cosmic-alignment, they've just grown in intelligence and number.) Alarmed, the authorities dispatch a team of two scientists to the region of infestation to investigate what's going on. One of the scientists is a middle-aged British biologist named Hubbs--he was the one who originally noticed the ants' weird behavior. And the other scientist is a young cryptologist named Lesko, whom Hubbs hired in the hope that he would be able to decipher the ants communications and discover their intentions. The two men set up shop in the middle of the desert in a sealed geodesic dome equipped with poison sprayers and the best Seventies-Era technology government money can buy. Then they sit back and wait for the ants to make their first move...

Things don't go entirely as planned however. A tragic accident involving one of their experiments results in the death of most of a farm family. Its lone surviving member--a teenage girl named Kendra-- is forced to take up residence with the two scientists to await transportation out of the area. Things get worse when the ants sabotage the scientist's communication console, effectively cutting off everyone's sole means of escape. This might not have been a problem had the ants not proven themselves to be highly poisonous, and capable of building deadly traps. The humans aren't completely helpless--they have the science and ingenuity to counter the ants' measures. However, it remains to be seen which species will have the skill and intelligence to win the upcoming battle, much less survive it...

The film is regarded by many to be an underrated classic. Despite a potentially goofy-sounding premise, Bass manages to put together a suspenseful, deliberately paced film that has the viewer on the edge of their seat, eagerly awaiting whatever move either side will make next. It also features a lot of innovative close-up footage of ants who are so expertly manipulated and filmed that one might actually think they do possess human intelligence.

Although Phase IV once appeared on Mystery Science Theater 3000 during the KTMA days, it wasn't so much because of its quality as it was because of its sci-fi subject matter, its strange, ambiguous ending, and the fact that KTMA just didn't have a whole lot of movies in its library to choose from. (Pretty much anything they had that was remotely science fictiony --or remotely related to the Mystery Genre for that matter--wound up on the show.)

Not to be confused with the suspense movie Phase IV, which came out in 2001.

Tropes used in Phase IV include:

Animal Nemesis: Hubbs develops this mentality, after the ants have poisoned him. It starts with him merely wanting to "teach the ants their place" and ends with him ranting and destroying everything in sight so he can kill a single ant whom he feels is spying on them.
The Chessmaster: While the humans put up a valiant effort, the prize has to go to the ants, who somehow manage to figure out and sabotage human technology, as well as build traps that would make Jigsaw proud.
Eek! A Mouse!: Kendra screams when she sees a mouse wandering around in the desert via a closed-circuit video screen. Then she and the other characters gape in horror as they watch the ants quickly devour the entire mouse in a matter of seconds.
Evil Brit: While Hubbs certainly isn't evil, he doesn't seem all that concerned about the deaths caused by one of his experiments. He's more interested in fighting the ants than he is in showing the proper amount of tact for his actions. (Of course, he's right about the ants and is justified in wanted his experiments to continue, but he should have done more than just shrug and say "Oh well," upon seeing the bodies of his experiments' unintended victims.)
Fake American: Lynne Frederick, whose English accent can be heard to slip in from time to time.
Fan Service: Lynne Frederick (Kendra) was definitely very cute in a Seventies sort of way. One sequence follows an ant up close as it crawls through her clothing, giving the viewer an ant's-eye view of Kendra's...um...assets.
Gainax Ending: And how. Saul Bass wasn't happy with the ending of the film, but Executive Meddling forced him to do it this way.
Hey, It's That Voice!: Kendra's grandmother was the voice of "Mother" in the first Alien movie.
The Narrator: Both scientists exposit via voiceover at some point, usually in some sort of "Captain's Log" manner.
Sanity Slippage: Kendra's grandmother after the ants have driven them out of their home. And of course, there's also Hubbs, who slips in and out of delirium after a poisonous ant bite has left his arm painful and swollen.
Stuff Blowing Up: The ants begin constructing large towers and also solar reflectors to heat the laboratory. Hubbs constructs a homemade grenade launcher to take care of this.