The fourth episode of the science fiction series Man From Atlantis airs on NBC, starring Patrick Duffy and Belinda J. Montgomery. Basketball superstar Kareem Abdul-Jabbar guest stars. 
Investigating an unusual underwater vortex with the Cetacean and its crew, Mark discovers a diver unconscious on the ocean floor. The injured man, treasure hunter (and swindler) Jack Muldoon, has been through the vortex, and says there’s dry land, with a wealth of gold, on the other side. Mark convinces Muldoon to guide him through the vortex, discovering an arid desert where water is present, but completely invisible. A giant named Thark uses the water to mine for gold, but the gold Muldoon has gathered has all been stolen from Thark. For both Mark and Muldoon, convincing Thark to close the flow of water is a high-stakes game: Muldoon has a fortune in gold to gain, and if Mark can’t get Thark to help, the world’s oceans may be drained into Thark’ strange realm.
written by Michael Wagner
directed by Richard Benedict
music by Fred Karlin
Cast: Patrick Duffy (Mark Harris), Belinda J. Montgomery (Dr. Elizabeth Merrill), Alan Fudge (C.W. Crawford), Ted Neeley (Jack Muldoon), Kareem Abdul-Jabbar (Thark), Richard Laurance Williams (Jomo), J. Victor Lopez (Chuey), Jean Marie Hon (Jane), Anson Downes (Allen)
Notes: At the time of his appearance in Man From Atlantis, NBA all-star Kareem Abdul-Jabbar was dividing his time between playing center for the Los Angeles Lakers and, in the off-season, his budding acting career. This was
only his third on-screen appearance; his next would be in the 1980 cult classic comedy Airplane!, with later appearances in Diff’rent Strokes, Fletch, Tales From The Darkside, and 21 Jump Street. And it wouldn’t be an American SF series of the ’60s or ’70s without a visit to Vasquez Rocks, “invisible water” and all.
LogBook entry by Earl Green