The Monolith Monsters (1957)

The sleepy town of San Angelo is in danger after a giant meteor crashes nearby in the classic sci-fi thriller The Monolith Monsters. Strange black rocks from the event litter the town and nearby geologists are unable to identify the unusual specimens. When the alien monoliths interact with water, they grow to terrifying, gargantuan dimensions and petrify anyone in their path. It is up to one of the geologists and a dedicated professor to stop their path of destruction before they plow humankind into a stone-cold early grave.