A frustrated Boston detective searches for the maniac responsible for mutilating a number of university coeds.
People are dying mysteriously and gruesomely, and nobody has a clue what the cause is. Only health worker Mike Brady has a possible solution, but his theory of killer slugs is laughed at by the authorities. Only when the body count begins to rise and a slug expert from England begins snooping around does it begin to look like Mike had the right idea after all.
After a meteor-like object lands in the woods, poachers unearth a cave filled with alien eggs. As they attempt to destroy the eggs, one of them is killed by an unseen creature, leaving one egg intact. A young boy named Tommy finds the remaining egg and brings it home to hatch. As more murders occur around town, Tommy learns that his new pet alien, who he names Trumpy, possesses telekinetic powers.
