Overview
"Tourist Attraction" is an episode of the original The Outer Limits television show. It first aired on 23 December 1963, during the first season.
Plot
Domineering millionaire John Dexter drives a group of explorers and scientists to pursue an ancient lake monster that is reputed to live in the waters of a South American dictatorship. Using underwater detection equipment aboard Dexter's yacht, the creature is spotted swimming along the lake bed. After several attempts, the creature is captured and taken to the local university for study.
The creature is immobilized and stored inside a freezer to aid in its preservation while out of water. Meanwhile, Dexter makes plans to transport it to the United States to place it on display. San Blas' absolute ruler, Juan Mercurio, has his own plans to use it to attract tourists to his country's faltering World's Fair, claiming the animal as a national treasure. During its captivity, the creature is revived due to an inept guard's negligence, and emits ultrasonic waves that cause the freezer door to implode. It is recaptured before it can fully escape its confines, and an armed guard from Mercurio's palace is ordered to stand watch. Dexter overpowers him, and arranges for the creature's transport on his private plane back to the States.
As Dexter and his assistants prepare the monster for its trip, they are shocked to see more of the creatures emerging from the lake. A marine biologist, previously employed by Dexter, urges them to turn the creature loose. Reluctantly, they comply, watching as it joins the others. Dexter, shooting at the creatures in an effort to stop them, is abruptly halted by a piercing, ultrasonic pulse. The creatures crawl back into the lake and disappear under the water. With the combined energy of their earth-shattering sound waves, the creatures topple the dam created by Mercurio during his reign of power, killing him, and flooding San Blas, destroying all that he had built.
From Wikipedia (CC BY-SA 4.0).