The adventures of the crew of marine biologists on the Endeavor, a 220-ton windjammer, as they explore, encounter various creatures and do research in the Great Barrier Reef off the East coast of Queensland. The ship's commander was Captain Ted King.
The show was filmed on location at the Barrier Reef in Queensland and shot in 35 mm. Lee Robinson, producer/writer/director for the series, was one of the great documentary makers during the 1940s. Robinson is best remembered for his production of Skippy, an Australian series from the mid 60s about a bush kangaroo. (Thanks to Peter Goed, Archivist for the Redcliffe Picture Palace in Redcliffe, Queensland, Australia for corrections and additional information).
No official videos have been released (as far as I know). The series was reaired in Canada in the early/mid 90s, so copies of episodes (including those that didn't air on Saturday mornings in the US) are available through collectors.
For more information on finding this and other Saturday morning shows on video, click here.