Phase IV (1974)
Basically a feature film with music video sensibilities and no music. Not a joke—the director mostly made title sequences for other films. The design's great: the superficially-ordered but amorphous lab in the geodesic dome, the unearthly insect monoliths, the hapless farmhouse with the Leiningen Versus the Ants-style firewall. The ant footage is fantastic, from the council to the graveyard to the queen. As for the acting, well, the performances aren't amazing, but at least their solid and understated realism doesn't get in the way of expressing the problems of modernist rationality and human dominance over—versus integration into—the natural world. Finally, the original ending is mind-blowingly off-piste. Just make sure you watch the dubstep version.