South Pacific Ocean, 1963.  The number on the Destroyer’s bow is 944, but a life preserver shows the number 946.  Guess if you’re drowning it wouldn’t make much difference to you.

The bridge crew is kind of an all-star cast depending on how you define star — The Incredible Hulk (not him . . . no, the other guy . . . no, the other other guy . . . no, before him), Kolchak‘s editor, Panicky Pete from The Corbomite Maneuver and Gomer Pyle’s commanding officer.

Captain Beecham goes below to have a chat with the Chief Bos’n’s Mate about the missing letters in his title.  If I ever had a opportunity to use the word fo’c’sle, this would be it.  But I got nothing.

Beacham is sympathetic toward the CBM, which is surprising as Simon Oakland usually portrays hotheads.  Chief Bell is distracted for reasons tied to a mysterious object that the ship’s sonar has located the titular 30 fathoms below.  Even more strange, is a metallic clanging that seems to be coming from the object.  Even more stranger, it is audible to other crew-members who are not listening to the sonar.  This is too much for Chief Bell who passes out on the deck.

Bell is not the only one affected. The rapping causes the other sailors to gaze lovingly into their crew-mates’ eyes.

Beacham orders diver McClure to go down to investigate.  McClure is lowered over the side in a suit that looks like Captain Nemo would have used it (I don’t know, maybe it was state of the art in 1963).  While on the ocean floor, McClure hears the rapping which sounds like a retired New York City cop banging on the inside of the hull near the propeller shaft.

McClure reports back that he bets his life there is someone inside that sub.  He says the sub seems to be — tee hee — stuck in deep, but not tight.  In some blatant padding that the hour-long Thriller seemed not to resort to, Beacham orders McClure to dive again.  McClure sees a 714 on the hull and the Captain finds it registered as a sub which sank in the area 20 years earlier.

This is the most offensive rapping Bell has heard from a vehicle without spinning rims.  At first it just causes a restlessness in him, and later he is actually seeing ghostly images of crewmates who died when he was the sole survivor of a sinking ship. They seem to be beckoning him to join them.

Beacham still thinks there might be someone in the sub.  He proposes “kicking the door in” apparent forgetting that it is under water, under great pressure, and metal.  One of his officers reminds him of these facts and he opts to radio the fleet for a rescue vehicle instead.  This is really a bonehead comment by the otherwise intelligent Captain.  I suspect it was more padding to get this episode up to an hour.

Still running short, Serling — I mean, Beacham — sends McClure down for a third time to investigate the rapping.  If only there were some sort of code that could be used to communicate through the sounds.  McClure surfaces and shows the captain a set of dogtags that he found below — with Chief Bell’s name on them.

Beacham confronts Bell with the tags.  Bell says he lost them 20 years ago when his sub sank — the one now below them.  He made a mistake with a light filter and the Japs sank the sub, leaving only Bell as the survivor. Now the crew is calling him to join them.  Wracked with guilt, he escapes the sick bay and dives into the ocean.

Rather than anyone diving in after him, or even tossing out the mis-numbered life preserver, the ship seems to scramble everyone in the crew and at a glacier’s pace lowers a boat full of men to pursue him . . . very sloooowly lowers them.

McClure takes a forth trip down and actually enters the sub.  There was a loose piece of equipment that could have made the clanging.  Or maybe it was the sailor who died with a hammer in his hand.

This was a fine episode that would have made a great 30-minute Twilight Zone.  Or, dare I say it, the variable Night Gallery length would have served it well.  It looks great, being filmed on an actually ship instead of the cardboard sets we sometimes get.  The performances are uniformly — ha! — great, especially from the surprisingly compassionate Captain and the tortured Chief.

Despite the bloat, I give it 25 fathoms.

Post-Post:

• This one reminds me of one of the all-time great concepts for a movie.  In Goliath Awaits, a ship sinks and somehow the passengers manage to seal out the water, manufacture oxygen and survive under the sea for years.  I’ve admired this plot for decades, but somehow never got around to watching the movie.  There’s no way it could live up to my expectations.  Oh crap, all 3 hours of it are on YouTube.
• I saw the credit for Lee Helmsman and thought it was the character’s name, or maybe a reversal of e.g. Helmsman Sulu; or like Minnie Driver.  But apparently it is a thing.
• Coincidence that the Chief’s name is Bell, and the rescue equipment would be a bell.  There is no real point, so it is just an unnecessary distraction.