Caltiki, the Immortal Monster

In 1959, John Merivale stars as Dr. John Fielding, a delirious archaeologist whose group investigates Mayan ruins and stumbles upon a mysterious creature that is a shapeless, amorphous blob. As they try to uncover the secrets of the temple, they discover that the creature is connected to a comet and may be a sign of impending doom. The team manages to defeat the creature using fire, but the remaining pieces begin to multiply and spread across Mexico City, putting everyone in danger.