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• Plot Synopses

Admiral Jiggs Starke........Harold S. Stone 
Captain of Jefferson........Jay Lanin 
Lt. Commander Jackson.......Lew Brown 
Fowler......................Steve Harris

Hang the computer! I designed this submarine, I know how she works!--Harriman Nelson

Nelson is on board the submarine Neptune on its shakedown cruise. There are a few problems but nothing major, until suddenly they encounter some interference and collide with some sort of force field. They find themselves above an uncharted under water mountain range, deeper than the Marianis Trench. Surprisingly, they pick up electromagnetic radiation from the mountains below. Nelson wants to take some ore samples, so he and a crewmember, Fowler, go out in diving gear. The two men leave the ship. They don't see it, but nearing the ship is a giant man-o-war.

Unaware, the divers swim to the mountain range. Nelson starts to take ore samples.

Meanwhile, the Neptune is having problems; the controls aren't working properly and the ship is rocking.

As the divers return to the Neptune, they see the giant man-o-war descending on the ship, swallowing it up. As they watch, the sub explodes inside the creature. They head for the surface, passing through a cloud of small man-o-wars, and reach the surface. Fowler starts to panic, but Nelson is able to calm him, telling him they have to get out of the water--although it is full of tiny stinging jellyfish, he is more worried about the rapidly approaching sharks! They take off their wetsuits and inflate them, tying them together to form a makeshift raft. Fowler seems weak, but he and Nelson climb onto the raft. Nelson says it's 300 miles to the nearest shipping lanes--he hopes it holds together.

Admiral Jiggs Starke calls his aide, Lt. Commander Jackson, into his office. He wants to know why the U.S. 7th Fleet can't find the Neptune; he and Nelson went through Annapolis together and he is concerned. Crane arrives, greets Jackson in the outer office, and asks to see Starke. Jackson tries to dissuade him, saying it is not a good time, but Crane insists and is admitted to Starke's office. He asks if there has been any news of Nelson; Starke says there has not, adding that if anyone could survive whatever happened, Nelson could. A message comes in on the teletype and Crane and Starke go to read it. Crand starts to read it aloud, but Starke stops him, snapping "I can read, Commander."

Nelson and Fowler lie on their raft in the hot sun. Nelson tries to determine their location; Fowler seems disoriented. He asks Nelson how long they can last; Nelson says that it depends on the individual, but at the same time is fashioning crude fish hooks. He jumps as he is stung by a small jellyfish, and Fowler shows him the many welts he received while in the water. When Nelson tells him to keep the wounds cool, Fowler cups seawater in his hand and applies it to his arm--and starts to drink it! Nelson stops him, and soon has managed to catch a fish.

Elsewhere, Stark is pushing for a continued search; when Crane says they don't even know if there were any survivors, Stark asserts that if anyone could have survived, it would be Nelson.

Nelson and Fowler are weathering a storm. They try to steer the raft, but Fowler is confused, not even knowing which way is port. He comments on the giant size of the jellyfish that swallowed the Neptune; Nelson attributes its size to the force field--something about it must have stimulated the creature's growth. The two men try to sleep.

In Starke's office, Crane paces--there must be something they can do! Just then, a message arrives. The search has been called off because of a storm.

Fowler is lost in the storm. Nelson tries to find him, but he is gone.

On the docked Seaview, Crane paces the observation nose. Morton enters and greets him; there is a call from Starke--the Seaview has been placed in temporary commission and is to investigate the loss of the Neptune. Starke says he will be on board within the hour, and tells Crane to tell the crew that he runs a tight ship, "all Navy, spit, polish, and the brig." Starke ends the conversation, and Crane says "That's all I need--Captain Bligh!" and slams his hand on the desk.

Later, Starke is drilling the missile crew, who unfortunately take two seconds too long to complete the drill. Crane tells him to take it easy--the Seaview isn't a Navy ship. Starke reminds him that the ship is now on active status. A call comes in for Crane--wonderful news! Nelson has been rescued and is waiting to be picked up at Honolulu Naval Hospital. He asks to talk to Starke, who tells him that he has been trying to pound some navy discipline into his crew; Nelson is not impressed.

At the hospital, Nelson is dressing. Talking to Crane, he seems agitated, talking nonstop. He almost forgets the cortisone he has been prescribed on his way out; the hospital wants him to stay for more tests, and Crane wonders if that might be a good idea, but Nelson says all he needs is the sea air.

As Nelson boards the Seaview, the men applaud. Starke tells him there's no one he'd rather turn over command to, and Nelson stiffens, saying that Captain Crane is in command of the Seaview. "Not while she's in the Navy and there are two admirals aboard--right, Captain?" says Starke, addressing Crane, who doesn't reply. There's a bit of an awkward moment, and then Nelson says to get underway--the sooner the mission is over, the sooner the Seaview will be a civilian craft again. He pours some pills into shaking hands and takes them. He and Starke exit, Starke asking Nelson about the Neptune. Nelson asks Crane to join them for the briefing as soon as he has cleared the harbor.

Nelson and Starke are talking. Nelson is jittery, saying that he is sure the Neptune's accident was caused by human error. Starke asks about the man-o-war and Nelson says it wasn't one creature but millions, combining to form a single organism, o ver 1000 feet across. Starke seems unconvinced and wonders if Nelson might be exaggerating; Crane says that Nelson doesn't exaggerate, and compares the giant man-o-war with the Seaview (individuals on the inside working together, one giant entity on the outside).

Crane and Chip Morton are in the corridor, Crane telling Morton to fix something in the electrical system, calling him by his first name in the process. Starke, passing by, hears this and calls Crane over, calling him lax and informal. Crane points out that he and Morton are friends, and that although he certainly refers to him as Mr. Morton in front of the crew, alone he calls him Chip. He says also that it is up to the captain to set the tone aboard a ship. Starke considers that reply insubordinate--just then, Crane is called to join Nelson in the control room.

In the control room, the controls are going crazy--just, says Nelson, as they did on the Neptune. Nelson orders the Seaview taken to the spot where the Neptune was lost. He stiffens, seemingly in pain; Crane asks if he is all right, and Nelson replies "of course" but takes another pill. Suddenly everyone is thrown forward as the currents affect guidance control. The sub is sinking and the crew can do nothing about it as the controls aren't working correctly. Crane looks to Nelson , who seems distracted, drawing pictures of jellyfish. Crane says that if they can't reach a plateau they will sink to the ocean floor; they see one, aim for it, and land. Starke calls it a dangerous maneuver.

Nelson thinks he has figured out the force field, and sends out divers to take an ore sample. He tells Starke that Crane is the best there is; Starke seems unimpressed.

The divers go out. The giant man-o-war appears. Starke tells Nelson that Crane is insolent; Nelson replies that Starke doesn't like Crane because he can't scare the pants off him.

The divers return to the ship. Crane, searching for a way out of their predicament, takes a computer printout and reads it--"Flood ballast tanks, full dive on all planes." In their current situation diving would not seem to be the best plan, but the com puter disagrees.

The divers enter the ship. They are covered with jellyfish stings which appear to be radioactive, and are sent to sickbay. The doctor says the radiation is so powerful it could destroy brain cells. Nelson comments that Fowler was attacked by jellyfish just before boarding the raft--that must be what killed him. He takes another pill.

As it happens, Nelson was correct and the ore samples confirm it. Starke says there is only one problem now--they have to get going before the man-o-war attacks again.

In the control room, Crane and Morton discuss the situation. Once they get off of the plateau they will drop, unless they can build up maneuvering speed. The computer recommends that they dive to 4500 feet (50 feet above crush depth) to build that momentum. Morton asks what Nelson thinks, and Crane replies that he hasn't shown him the data yet. He asks Morton if Nelson seems different, but Morton doesn't have a chance to reply--just then Nelson and Starke rush in, Nelson all excited about the ore. Crane tells him what the computer has come up with. Nelson thinks that's crazy, telling him to take the ship up instead. When Crane seems hesitant, Starke tells him that it's an order. Crane tries to reason with Nelson, reminding him of their conversation at the hospital, when he told him how the Neptune foundered because it had lost maneuvering speed. Nelson denies ever having said that, and relieves Crane of command. Crane says that as captain of a private vessel he cannot be removed; Starke ( again) points out that the Seaview is currently a Navy ship. By now Nelson is really angry. He orders Morton to escort Crane to his cabin, which he starts to do--when Crane turns and punches Morton in the stomach, pulls a gun on the admirals, and asserts that the Seaview is his responsibility. He orders the crew to do as the computer recommended. Nelson pleads with him not to, saying "Lee, don't...it's down there!"

The computer is right, and the Seaview is saved. As they ascend, Nelson turns on Crane, shouting at him, accusing him of betrayal. Crane leaves. Nelson orders Morton to take the Seaview home, giving him command. He tells Starke that Crane mutinied, demanding a courtmartial. Starke points out that Crane was right, and his actions saved the ship, but Nelson is becoming hysterical and Starke takes him to his cabin. As they go, Nelson mumbles to Starke that he was right and the Seaview is a loose ship. He turns to the control room crew and shouts at them, calling them mutinous.

In his quarters, Crane sits on his bed. The ship's doctor eners--one diver is dead, having gone crazy and then gone into a coma. The other diver seems all right but may yet develop symptoms--talkativeness, depression, irritability--and just before enter ing coma, there may be a violent episode. Eventually death would come, as irradiated brain cells are inevitably fatal. Making the obvious connections, Crane says "oh, no" in horror.

The man-o-war has returned. Starke orders Crane to the control room, where he finds Nelson sitting and staring into space. The doctor leads Nelson away. Crane looks through the periscope. He tells the reactor room crew to prepare a full charge--they'll hit the creature with an electric shock. They wait until the Seaview is inside the creature, then send a shock to its central nervous system. The Seview glows, and the creature dissipates.

Crane and Starke go to sick bay. Nelson is fine--he had an allergic reaction to the cortisone that included some of the same symptoms suffered by the diver. Starke praises Crane's performance, telling Nelson he should be proud. Nelson says that he is, mighty proud.

The Seaview reaches the channel.

In the camp, the scientists are discouraged--all except Nelson.

In Schroder's headquarters, they watch on their viewscreen as the Seaview enters the channel.

In the camp, Nelson says "Now...now!"

Schroder's headquarters building explodes.

Later, on the Seaview, Nelson tells how he realized that Tomas was a traitor--there was no way he could have gotten out of the camp unless Schroder wanted him to--and fixed one of the bombs that Tomas had sabotaged, making a timer for it from his watch. Tomas had the repaired bomb with him in the control room when it went off. Morton enters the room with good news--after their long ordeal, the scientists are all right.