THE NEPTUNE FACTOR: that awful sinking feeling

If 1973's THE NEPTUNE FACTOR director Daniel Petrie hoped to cash in on the positive vibe surrounding the previous year's smash hit 'The Poseidon Adventure' by casting one of its stars in his underwater thriller he was desperately deluded.
There is nothing that Ernest Borgnine could have done to rescue this water-logged turkey.  Not even Gene Hackman in full preacher-hero mode could have saved this film. It is truly one of the all-time worst disaster/sci-fi movies ever made. Borgnine is actually one of the few good things about this project. He has barely anything to do and very little to say but at least he doesn't embarrass himself, which is more than can be said for the rest of the cast or the production crew.
The story focuses on the rescue mission launched to save the crew of an underwater laboratory which has rolled into an apparently bottomless trench on the sea bed after an earthquake. The only vessel capable of diving that deep is an experimental US Navy mini-sub piloted by the arrogant Ben Gazzara. We know he's arrogant because he wears a perpetual mocking sneer on his face. It's an expression Gazzara reserved for projects he knew were a piece if crap and unfortunately he wore it a lot in the 1970s (and I write that as a huge Gazzara fan who ranks some of his films among my all-time favorites).
Despite his air of insufferable superiority (and equally atrocious Atlanta, Georgia accent) Gazzara allows diver Borgnine and Dr Yvette Mimieux to join him aboard the surprisingly spacious mini-sub (more Winnebago than cramped submersible) as they plumb the depths in a desperate race against time to locate the missing lab before the trapped men's air supply runs out. Along the way they encounter huge and terrifying fish, never before seen by man, which threaten to destroy their fragile craft and devour the crew.
Now if all of this exposition has given you the impression that THE NEPTUNE FACTOR is an exciting viewing experience I must apologise.

THE NEPTUNE FACTOR is excruciatingly dull. The story unfolds at such a leisurely pace that it's often difficult to discern forward motion, and the cast move as if heavily sedated. Gazzara may not be able to disguise his contempt but he's clearly not alone in recognising the fecal matter he's been given to work with. It's particularly sad to watch the venerable Walter Pidgeon (he was Mr Miniver for cripes sake!) struggling to summon the energy to deliver his next turgid line and repress the knowledge of what the film's doing to his reputation.
Not only is THE NEPTUNE FACTOR unforgivably dull it is also ludicrous.
Unable to match the budget for the special effects which had helped make 'The Poseidon Adventure'  such a box office hit, director Petrie is forced to improvise. Many of underwater diving scenes appear to have been shot in a swimming pool, and the terrifying monsters of the deep are actually blown-up (magnified) footage of the kind of small tropical fish usually found in a 10 year old child's bedroom aquarium. I believe the aquarium was also used for the long shots of the obviously toy mini-sub chugging along between the underwater weeds.
I wouldn't be surprised if the same 10 year old who supplied the fish also acted as the film's technical advisor. What else other than the innocent ignorance of extreme youth explains the sunlight streaming through the water FIVE HUNDRED FEET below the surface, and Borgnine's effortless ability to scuba dive at that depth without being crushed to death by the pressure (although it does have a slimming effect on the portly veteran actor, but I suspect that's mainly because the stuntman is half Borgnine's size)?
There's only one way to watch THE NEPTUNE FACTOR and that's on your own. Because it is just so bad that it's utterly impossible to justify to anyone else why they should sit through it with you.