Squirm (1976) (Blu-ray / DVD)

THIS WAS THE NIGHT OF THE CRAWLING TERROR!

One of the most original and entertaining of the revenge-of-nature films that characterised mid-1970s American horror, Squirm begins with a pylon being downed by a thunderstorm, sending millions of volts into the wet, conductive mud, which naturally gives hundreds of thousands of its wriggly inhabitants an insatiable hunger for human flesh.
And since the accident has also inconveniently cut off the electricity to Fly Creek, Georgia, its population could hardly be more vulnerable when the sun goes down. Houses can be barricaded against most intruders, but what happens when they're small enough to get into the water supply?
Writer-director Jeff Lieberman (who also made the cult classics Blue Sunshine and Just Before Dawn) achieves a near-perfect blend of knowing wit and good old-fashioned scares, with make-up genius Rick Baker (An American Werewolf in London) on hand for some of the memorably disgusting special effects.