Sea Hunt

From Wikipedia:

Sea Hunt is an American adventure series that was aired in syndication by Ziv Television Programs from 1958 to 1961 and was popular in syndication for decades afterwards. The series originally aired for four seasons, with 155 episodes produced.

The program followed the adventures of scuba diver Mike Nelson, an ex-Navy frogman turned freelance diver, played by Lloyd Bridges. He outmaneuvered villains, salvaged everything from a bicycle to a nuclear missile, and rescued a downed Air Force pilot (in his sunken jet, in the pilot episode), children trapped in a flooded cave, and even a dog. One unusual aspect of the series was that at the end of each episode, Bridges made a plea to protect the oceans.

After Bridges was cast, he was given a crash course on scuba diving by Zale Parry, and Courtney Brown, the latter would serve as his underwater stunt double. Over the course of the show's run, Bridges would get more involved in the underwater stunt work, graduating from close-ups in the earliest episodes, to doing all but the most dangerous stunts by the end of the series' run.

The series served as a stepping stone for some of Hollywood's most notable actors, including Leonard Nimoy, Robert Conrad, Bruce Dern, Larry Hagman, Ross Martin, Jack Nicholson (in the last episode of the series) and Bridges' own sons, Beau and Jeff. Russ Conway guest starred eight times on the series. Many lesser-known actors also appeared, such as Robert Karnes, Tyler McVey, and Gregg Palmer.

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