General Juan Mercurio is the current rules of the country of the Republic of San Blaz. On a lake, John Dexter is leading an underwater expedition, and impatiently asks Tom Evans for a demonstration of the sonar equipment. Lynn Arthur is with them and asks for someone to rub suntan oil on her back. Tom goes over to her, and John watches the sonar display. He sees a humanoid ichthyosaur-like creature on the camera monitor, swimming beneath the boat. He calls Tom over and says that he saw something and is going down. Tom catches a glimpse of it but dismisses it as a lungfish. John bets that it's no normal creature and dives into the water with a spear gun.
John swims down to the camera, and Tom and Lynn spot him. Tom explains that John came down and bought Tom's boat business when he refused to sell, and says that he's a marine biologist. Lynn says that he must be good if John kept him on, and explains that she came with a magazine that John purchased when they did an article he didn't like. She's the one who wrote the article, and John gave her a job as a secretary. Lynn sends John reports of his southern hemisphere holdings and "awaits his pleasure".
The ichthyosaur senses John approaching and remains hidden. When he finds nothing, John returns to the surface and Lynn reminds him that they have cocktails with Mercurio at 7.Tom declines to go with them, saying that he's meeting with Professor Arivello at the university.
At the manor where they're staying, John makes a call and says that he'll be in Rome in the morning to deal with some business troubles. The servant suggests that John see Mercurio's world fair, and admits that no one comes to it. John suggests that people don't want to come because of Mercurio's dictatorial well, and the servant warns him to watch his tongue. He explains that his brother-in-law criticized Mercurio a month ago, even though he built a dam for the locals and it's already crumbling. Lynn comes down and they go to Mercurio's palace. As they drive, Lynn says that John has only been there for three days in the last six months and now he's going to Rome. John insists that it's business, and when Lynn complains he says that she can fire herself because he won't.
The locals are celebrating in the streets with fireworks and dancing, and Mercurio is regaling his guests with anecdotes. John and Lynn arrive and Mercurio notices that John is wearing denim and tennis shoes along with his jacket. John says that he bought an underwater research firm , and notes that Mercurio is rich. Mercurio says that he only lives well because his people want him to and leads John into his study. He boasts of the clean streets and electric lights, and shows off a topographical model of the new city that he built and the dam that he developed to provide power and hold back the flood waters. John dismisses Mercurio's development, and Mercurio figures that John thinks that he's a tyrant. He wonders why people don't come to his world's fair, and asks John to have a few articles about San Blaz published. John says that isn't possible and Mercurio walks out.
Glancing around, John sees a small statue of a local god on Mercurio's desk and notices that it looks like the ichthyosaur that he saw earlier. Captain Fortunado comes in with Lynn and John asks him what the statue represents. Fortunado says that it's an ancient god prominent in the San Blaz folklore, and Indian fisherman claim that they've seen it from time to time. John tells Lynn that something came up and he's staying on in San Blaz.
The next day, Lynn flirts with Tom until John orders him to descend with him to look for the ichthyosaur. They pick up the ichthyosaur's sonic emissions and descend. An ichthyosaur finally advances on them and they shoot it. Thomas swims for the surface while John attacks the ichthyosaur with a knife. On the surface, Tom tells the crew what happened. John comes up and has the crew bring the ichthyosaur aboard. It's apparently dead of the knife wound John inflicted on it, and Tom has the skipper take a picture of it with John posing over its body. He insists that Tom stand with him, and then has crew refrigerate it so they can take it to the university marine lab. John gives the spear to Lynn as a souvenir
In the water below, two more ichthyosaur watch the boat go.
Later at the university, Arivello holds a press conference and says that native fishermen have found coelacanths in the past. The ichthyosaur is half as old as the world itself, and Arivello believes that the ichthyosaur evolved from prehistoric dinosaurs. Mercurio and his soldiers arrive and the general demands to see the creature. Mercurio goes into the walk-in freezer with the press, and John tells Lynn to get an insulated box so they can ship the ichthyosaur back to the States. Arivello explains that the ichthyosaur is amphibious and can survive on land for short periods. He says that there's no sign of the wounds that John inflicted, and Mercurio says that no one is to touch the creature or move it. He then poses with the creature for the press photos.
Lyn comes back and tells John that they'll be ready to go in the morning. Meanwhile, Arivello tells a man, Paco, to stand guard and let no enter the freezer. The professor shows Paco the thermostat and tells him to keep the temperature at zero.
That night, Paco's friend Oswaldo comes to the lab to keep Paco company. Noticing the cold, Oswaldo turns up the thermostat and sits down to play checkers with Paco. Inside the freezer, the ichthyosaur thaws out and awakens. It emits a sonic pulse, cutting through the door, and breaks out into the lab. Oswaldo runs out yelling for help, and the creature stuns Paco with its sonic emissions.
Oswaldo returns with the staff members and a soldier. The soldier prepares to shoot it, but Paco says that it could have killed him but stopped. Reconsidering, the staff has the staff net the creature and Paco tells them to bring Arivello.
Later, the staff suspend the ichthyosaur in a tank of water. John and Tom arrive and they discover that the ichthyosaur emitted a concussive force to cut out of the freezer. Tom figures that the ichthyosaur can emit a concentrated beam in a pattern, and is emitting a distress call. He suggests that they could speak to it like they "speak" with dolphins. A reporter notes that Mercurio believes displaying the ichthyosaur will make his world's fair a success, and Professor Arivello says displaying it as a tourist attraction degrades the scientific achievement.
John, Lynn, and Tom return to John's home and Tom points out that John let Arivello talk against Mercurio. John fires Tom, and Tom admits that he froze when they confronted the ichthyosaur that morning. Tom asks about Arivello, saying that he's scheduled to work with the man, and John tells him that he can do it but not as his employee. Once Tom leaves, Lynn says that she admires Tom's courage and asks John if it makes him feel powerful to think people are weaker than him. John tells her to back off, saying that it's not part of their deal, and Lynn tells him that she's been withholding love, pity, and tears, and John tells her that he doesn't need them. When she tries to go, John grabs her and they kiss briefly. Pulling away, she says that she used to love him but she can't love a machine and she needs to give love.
The next day, Tom and Arivello observe the ichthyosaur as it hangs in its harness. John comes in and asks how long until he can take it to the States. Arivello says that it's been talking to them and Tom demonstrates a two-way microphone that they've set up at the dam, and are hoping that another creature responds. The scientists pick up a school of the creatures... and they're getting louder.
At the damn, the creatures concentrate their sonic emissions on the dam.
Mercurio and his men arrive at the lab and the general says that they'll move the creature's tanks. He says that he's declaring the ichthyosaur a natural treasure, and John says that it belongs to him and he's made other plans. Mercurio puts a guard on the tank and tells him to shoot to kill if anyone touches the tank. Lynn and the crew arrive, distracting the guard, and John and Tom disarm him and John tells the crew to take the ichthyosaur to the plane. As they go, Tom tells John to let the ichthyosaur go back into the lake. He figures that the other creatures will try to rescue their comrade, and John says that what they do is Mercurio's problem. He tells Lynn to come with him and they go out to the truck. Lynn sees the creatures emerging from the nearby river and points them out to John. John opens fire on them as they approach but they concentrate their sonic beams on him. Tom has the crew release the captive ichthyosaur, and John recovers in time to watch it go back into the water with the others.
The dam collapses from the creatures' sonic bombardment and the waters pour into the city beyond. That night, the soldiers conduct relief efforts. John, Tom, and Lynn walk through the debris and John tells Tom that he looked good earlier but it isn't the compliment it used to be. Once he walks on, Lynn wonders if John thinks that he's a coward and Tom figures that John thinks it does. Lynn goes to him and smiles, and he says that they can play their relationship by ear. They leave together as the soldiers find Mercurio's body among his people.
Written by Gadfly on Feb 17, 2019