The crew of a lost submarine returns as rock men to menace the Seaview. A new man, Kowalski’s friend Richards, is captured on a diving mission and turned into a…

Twin scientists – one good, one evil – come aboard Seaview. The evil twin is out to create a radioactive “plant man.”

A ghostly ancestor of Admiral Nelson visits him aboard Seaview.

Seaview is investigating a thousand-mile wide communication blackout. The source of this is a large alien brain found under the sea. It is broght aboard and takes over visiting scientist,…

A foreign power is salvaging sunken nuke missiles from the ocean floor to make themselves a superpower.

Nelson and crew are invited to a marine scientist’s undersea lab for a visit but there is giant sea life in the way.

Seaview comes to the rescue of newly discovered WWII survivors living in an underwater cave beneath a rumbling volcano.

Mobster Frank Egan kidnaps the daughter of Dan’s friend and uses her as a hostage to force Dan and the team to break out a key witness, Augie Gorman, against…