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• Plot Synopses

Guest Cast:

Lars Mattson................Richard Carlson 
Sigrid Mattson..............Anna-Lisa 
Dalgren.....................Steven Geray 
Otto Hassler................Frank Richards 
Anderson....................G. Stanley Jones 
Proprietor..................Torben Meyer 
The Boy.....................Greger Vigen 
Gartern.....................Erik Holland 
Malone......................Mark Slade 
The Father..................Kort Falkenberg 
O'Brien.....................Gordon Gilbert

Sea monsters? Even if I saw one I wouldn't believe it.--Lee Crane

Three drunken men are carousing in a rowboat, playing the accordion and singing. Behind them, a giant tentacle unfolds from the water and goes under again, and we see the massive body it is attached to. Oblivious, the men continue to laugh and drink--until the creature capsizes the small craft and drags them under.

On the Seaview, Nelson, Crane and Morton are in the radio shack, listening to a news story about a Norwegian fisherman insisting that he was attacked, and his two friends were eaten, by a sea monster. Nelson asks Crane if he believes it; Crane responds that he wouldn't believe it if he saw it. Nelson replies that such a thing could be possible--there are depths man has never reached, and there's no way of knowing what exists down there. Later, another radio report is heard in which the survivor describes an animal very much, Nelson says, like an octopus--but in those waters, and in that size, that seems unlikely. However, the survivor's body is covered with circular welts and holes. Nelson orders a course set for Norway.

As the Seaview surfaces, the fishermen on the beach notice the sub's arrival. By the time Nelson and Crane are brought ashore by raft, the fishermen have gone, and they are met only by several reporters who are covering the story. The newsmen say that the villagers are closed-mouthed and superstitious, and they have had little luck getting information. They take Crane and Nelson to the house where the survivor is recovering from his injuries.

At the house, a woman checks on the patient, then leaves his room to answer the door. After she leaves, a man enters the room through the window and smothers the survivor with a pillow. In the other room, the woman, Sigrid, is reluctant to let the reporters see him again; however, when Nelson introduces himself, the doctor who has been treating the survivor welcomes him. They go to the survivor's room--and find him dead. Sigrid picks up a button from the bed and notes the open window.

Nelson and Crane go to the local tavern. As they enter, the music stops and everyone becomes silent. They go to Sigrid's table and ask to join her; she is reluctant but permits it. She is not a nurse, but the local schoolteacher, who was helping the doctor care for the survivor; now that he is dead, the doctor and the reporters have left town. She, herself, doesn't believe the story about the sea monster, putting it down to drunken visions. Crane says that it might be useful to find the boat, but Sigrid says that in the enormous fjord, it would be like trying to find a needle in a haystack. As the men leave the tavern, Crane comments that she seems as anxious for them to leave as does the rest of the village, and Nelson says he doesn't believe her explanation for the survivor's injuries. They pass a car, and as soon as they are out of sight, a white-haired man runs from the car to the tavern.

Nelson attempts to search the fjord with the minisub, but with no luck. He is planning to leave the area altogether, when the Seaview's sonar picks up some unfamiliar sounds. Nelson calls Chief Jones to the observation nose, saying the chief is a human sonar and if anyone can identify the sound, he can. As it turns out, he can't, but the sound reminds him of whales. Everyone finds that idea amusing--until they look out the window and see a large group of giant catfish! They surface, determined to continue their search. A young boy rows out to the sub, curious; Nelson calls a Norwegian-speaking crewman to translate. The boy knows nothing of any sea monsters, but says that the boat was not attacked in this fjord at all, but in an entirely different fjord. They had been given false information.

In the other fjord, Nelson sends out divers to search. The find the remains of the boat--and a piece of tentacle from the sea monster.

Watching the Seaview surface in the fjord are Sigrid, the white-haired man from the tavern--her uncle, Oscar Dalgren--and two other men--her husband, Lars Mattson, and his assistant, Otto Hassler. Hassler wonders if the Seaview has found the boat and tentacle; Mattson says it doesn't matter, as no one in the village will talk to them--they are paid too well for their help, and they share in the guilt for the deaths. He says he has done nothing he is ashamed of. Dalgren says that the experiments made sense at first, but not any more--and if they don't stop, he will go to the authorities. Mattson asks Sigrid if she will do likewise, and she says she will not, as he is her husband. Mattson says he will destroy his creation after the experiments are completed, and not before. He leaves, and Sigrid begs her uncle not to go to the police. He agrees.

On the Seaview, Nelson has determined that the monster is probably the result of a scientific experiment. He has requested information from Washington about any subscribers to scientific journals in this area, and there is one in town--an Oscar Dalgren. Nelson knows the name, but says he hasn't been heard from in ten years. He looks up an abstract of one of Dalgren's papers, having to do with breeding sealife in order to provide food at little cost.

Nelson and Crane go ashore, visiting the tavern again. They talk to the proprietor, who insists there is no Oscar Dalgren in town. Nelson replies that he knows that there is, and tells the proprietor that, next time he sees Dalgren, he should tell him Nelson knows all about him and his experiments. Crane says that was a wild shot; Nelson replies that it was, but if he's right things should start to move.

On the beach, Nelson and Crane are discussing the situation further when a boulder is dropped on them--it's close but it misses. They take cover behind a large rock, and then are shot at. Crane goes to look for the sniper; when he finds him, they fight and fall to the beach below. Questioned, the man denies knowing any Dalgren, claiming a stranger paid him to scare them away. He gets away; Crane starts after him but Nelson says to let him go--he wants to see what they try next.

Mattson is looking into a pool at his creation; he climbs a ladder, opens a trap door, and enters the room. Hassler says he's taking a chance going down there; Mattson replies that he rather enjoys it, and besides, his child must be fed. Sigrid enters and tells Mattson that Nelson knows about her uncle and their experiments, but that her uncle doesn't yet know this; Mattson says that as long as they keep Dalgren away from Nelson, all will be well. The experiments will be over in a few months and then Sigrid will surely agree that it was all worth it. Sigrid tells Mattson about the button she found, accusing him of killing the survivor. He can't look her in the eyes; he tells her he had to do it--he couldn't just throw away all his years of work. He asks her to understand; she says she tries to.

The Seaview's sensors detect a small object; it's a diver, attaching a ticking device to the ship's hull. Nelson and Kowalski go out in diving gear to remove it; the diver, hiding, watches them. Kowalski returns alone to the ship, Nelson having followed the diver--he has the device, which is just a spring-loaded timer. Crane says it is a trap for Nelson, and orders all available divers to the missile room.

Nelson follows the diver, who continually looks back to see that Nelson is behind him and never gets too far ahead, into a cave and up--into the pool where Mattson fed his creation. Nelson climbs out and goes up the ladder, but when he opens the trap door, he finds a gun in his face. Mattson introduces himself; Nelson remembers his name--Dalgren's assistant. Mattson says he was formerly Dalgren's assistant, but that the experiments are his, not Dalgren's. He introduces his assistant, Hassler, who served as the bait to bring Nelson here, and shows Nelson around the laboratory, describing the work he has done. When Nelson asks what role Dalgren has played in the research, Mattson insists that the work--and the credit--are all his own. He had lived long enough in Dalgren's shadow. Now he plans to send his creation into the fjord where the Seaview is, to test its resistance to attack. Sigrid and Dalgren knock on the door and enter; when he tells them he is going to let the creature out, Dalgren calls him crazy--Sigrid has told him about the survivor's murder. Mattson orders Hassler to take them below, going down himself first. Dalgren attacks Hassler, and Nelson continues the fight; in the confusion, the gun goes flying and Sigrid picks it up and turns it on Mattson, begging him not to let the creature out, saying she will shoot if he does. He does, and she shoots; he falls into the water and is devoured.

Nelson radios the Seaview, to tell them to get to open water, but by the time he gets through, it's too late and they are under attack by the giant octopus. The creature is crushing the ship. Nelson tells them to bring their reactors to full power and shoot a charge through the hull. They do so, shocking and killing the creature, which sinks to the bottom of the fjord. Nelson tells them to surface and send a raft ashore to pick him up. Crane asks him if everything is all right; Nelson, looking at Dalgren and Sigrid, says that it will be.