The science fiction TV movie-of-the-week Man From Atlantis airs on NBC, starring Patrick Duffy and Belinda J. Montgomery. Created by Mayo Simon and classic Star Trek veteran Herbert F. Solow, Man From Atlantis centers around a mysterious man from the ocean (Duffy) discovered by humans, who find he is willing to live among them and coexist for peaceful purposes. Three more TV movies will follow, each successful enough for NBC to greenlight a weekly series in the 1977-78 season. 
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An adult, seemingly human, male washes up on the beach among seaweed and other flotsam after a storm, and is rushed to a nearby hospital, where his oddly mottled skin, webbed hands and feet, unusual eyes, and especially his apparent inability to breathe pure oxygen have emergency doctors stymied. Dr. Elizabeth Merrill of the Foundation for Oceanic Research notes the man’s unusual conditions are more akin to sea life than life on land, and suggests returning him to the ocean. Once in the water, his health is restored. A fascinated Dr. Merrill continues to study him, finding that while he tires quickly on land, he has enormous strength under the water, and can dive to depths of tens of thousands of feet. He can also, with intense concentration, exert his willpower onto human beings. She concludes, not entirely jokingly, that he may be the last citizen of the lost underwater civilization of Atlantis.
But when the Navy catches wind of Dr. Merrill’s research, a Navy Admiral begins hatching plans for the unusual man from the sea – given the nondescript human name Mark Harris – to take on hazardous undersea bomb and mine disposal tasks. Mark only reluctantly agrees, but during his first big mission, to locate the wreckage of the lost research submarine Seaquest, he swims to depths unsurvivable by human divers and sees a perfectly intact futuristic sub. Mark boards the sub and returns with it to an undersea mountain base, commanded by Mr. Schubert, a rich ocean salvage man who is using his wealth and various found pieces of secret equipment to plot the end of 20th century civilization…after which he will, naturally, emerge as the new ruler of mankind, promising peace and prosperity (but no free will) to his hand-picked community of scientists. Even an outsider to human society like Mark Harris realizes that Schubert must be stopped at any cost.
written by Lee H. Katzin
directed by Mayo Simon
music by Fred Karlin
Cast: Patrick Duffy (Mark Harris), Belinda J. Montgomery (Dr. Elizabeth Merrill), Dean Santoro (Ernie Smith), Art Lund (Admiral Dewey Pierce), Victor Buono (Mr. Schubert), Lawrence Pressman (Commander Phil Roth), Mark Jenkins (Lt. Ainsley), Steve Franken (Doctor), Joshua Bryant (Dr. Doug Berkley), Allen Case (Lt. Commander Johnson), Virginia Gregg (Whale Scientist), Curt Lowens (Emil), Charles Davis (British Scientist), Lilyan Chauvin (French Scientist), Vincent Milana (American Scientist), Alex Rodine (Russian Scientist), Philip Baker Hall (George), Marguerite DeLain (First Receptionist), Trudy Marshall (Woman at party), Michael J. London (Popeye), Robert Dore (Diver), Michael Watson (Diver), Connie Izay (First Nurse), Judd Laurance (Intern), Jim Chandler (Man on beach), Patricia Anderson (Second Receptionist), Akemi Kikumura (Third Receptionist), Larry Holt (Ambulance Diver), Peter Weiss (Test Lab Assistant), Robert Phalen (Habitat Technician), Maralyn Thoma (Second Nurse), Phillip Roye (Intern), Cheryl Robinson (X-Ray Technician), Scott Stevenson (Boy on beach), Philip Tanzini (Boy at phone booth)
Notes: Scenes from the pilot movie were filmed aboard the U.S. Navy dive ship Elk River IX-501. Executive producers Herbert F. Solow and Robert Justman were veterans of the original Star Trek series, though Solow was now working under his own banner, Solow Productions, at this point, since Desilu had long since transformed into Paramount Pictures’ TV division. This was the first of four feature-length TV movies-of-the-week introducing the Man From Atlantis characters and concept; the ratings success of these movies would guarantee the concept an additional, but brief, single season of hour-long episodes in the 1977-78 prime time season.
At roughly the same time as the initial movie aired, NBC (the network home of Man From Atlantis) was also airing the short-lived fantasy series The Fantastic Journey, which involved an island that may or may not have been Atlantis. This was more of a coincidence than anything: “unexplained paranormal phemomena” were all the rage in the 1970s, whether the lost city of Atlantis, ESP/telepathy, UFO sightings, or stories of crystals vibrating with energy. That the missing research vessel was named Seaquest – same as the advanced sub from the 1990s NBC series of the same name – is also a coincidence, though those wishing to connect some unlikely dots in fan fiction are welcome to do so.
LogBook entry by Earl Green