The ghostly Captain Krueger returns, still plotting to have Crane killed so that he may take over Crane’s body, but will Nelson succumb to Krueger’s diabolical demands?
Peter Omir, a super-human android, will stop at nothing—not even the annihilation of the planet—in his quest to mine a powerful new element from the Earth’s core.
In the absence of Admiral Nelson, Admiral Park takes his place as a crazed scientist creates a giant, menacing creature that is half-man and half-fish.
While on a mission to recover dangerous fuel cylinders from a wrecked submarine, the Seaview is attacked by an enormous sea spider, and with Nelson gravely injured, it’s up to Riley to help save the day.
The body count aboard the Seaview mounts as the damaged ship becomes part of a sinister plot to sabotage a seven-nation peace conference.
Crane is held captive on the Isle of Death as the Flying Sub is attacked by a mysterious underwater pirate ship.
The President’s life is endangered by the subject of a bizarre experiment, a gigantic whale that has swallowed an atomic bomb.
It’s a race against time as the Seaview is imperiled by a scientist desperate to retrieve data pertaining to a miraculous youth serum from his sunken ship.
When the Van Allen radiation belt catches fire, Nelson’s plan to extinguish the blaze is thwarted by a misguided U.N. official.
The crew of the Seaview is haunted by a phantom U-Boat and her ghostly captain.
As two escaped convicts plot to hijack the Flying Sub, the Seaview is menaced by a monster from the deep.
With Crane being held hostage, Nelson leads the fight against a sinister foreign power intent on stealing undersea defense missiles.
Commander Crane leads the rescue mission as Admiral Nelson and Chief Sharkey struggle to survive on a mysterious island inhabited by deadly prehistoric beasts.
While on a mission to retrieve an unmanned space probe, the Seaview is taken over by a deadly extra-terrestrial organism.
The Seaview races to the rescue when rogue drone submarines begin attacking the Eastern United States.
In order to rescue a kidnapped scientist, Nelson infiltrates a mysterious toy company serving as a front for an enemy spy ring.
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