Part of me doesn't know how to rate this, because I saw it years and years ago, but it's one of those films which left a vivid impression on me. "Impulse" is the story of a town who due to an unknown chemical in the milk supply(the townspeople never know) begin to lose all impulse control.
What follows are increasingly disturbing scenes, which flow into each other, blankly, as a sheriff opens fire on young delinquents, a mother watches nonchalantly as her children light one of her friends on fire, doctors turn off life support, and sexual laws and norms completely breakdown. It's a bleak film, where impulses like curiosity, the desire to save others, are spare, and sex and violence all but absolute by the films apocalyptic end, involving a government cleansing with a crop duster. One of those odd sci-fi films you watch late at night and confuse for a dream till see the box in the video one day. Be interesting to take a second look.