Yes, this is a rip-off of Jaws, with a giant octopus in place of a great white.
But isn't Jaws itself a rip-off of Moby Dick, with the shark being less a natural creature than a supernatural one embodying our collective fears about nature, the return of the repressed and all that?
Wasn't making rip-offs what the filone cinema was all about anyway?
Now you see him...
Now you don't
Another early victim is the one-legged old salt/Ahab/Quint type
And doesn't Tentacles also work its own variations upon its model, one of which – the monster's going after the kids as they sail – actually seems to have been taken up by Jaws II, an film which, along with III and IV, exemplifies Hollywood's own less than perfect record when it comes to opportunistic cash-ins?
Now you see it...
Now you don't
Likewise, doesn't the fact that the octopus can grab victims from above the surface and sucks their flesh and marrow away add its own frissons; It's not so much “Just when you thought it was safe to go back in the water... “ as “It's not safe to even go near the water”
Another variation is the splitting of the evil businessman / politician type into two. On the one hand we have the President of Trojan Construction, played by Henry Fonda. On the other we have his underling. While Fonda defends his company he's horrified to learn of his underling's corners-cutting on a tunnel – the one that's led to all the trouble.
Other US actors collecting their paychecks are Shelley Winters and John Huston, who in his other career had actually directed a version of Moby Dick.
They're cast opposite a number of familiar Italian faces and names, including Franco Diogene and Sherry Buchanan, while Stelvio Cipriani contributes the score. Whether out of economy, laziness or environmental concern, some of his cues seem recycled from What Have You Done to Your Daughters.
Sherry, in uncharacteristically exploitation-avoiding image
Franco, the comedy fat man as per usual
While Ovidio G Assonitis / Oliver Hellman is clearly no Steven Spielberg, he does a decent enough job. There is plenty of underwater action and some nice colour work, with yellow and blue contrasts often being used, the budget obviously being large enough to allow for a reasonably broad canvas.
A world without red
A real octopus
Inevitably the scenes with the octopus are variable: Sometimes you can tell it's a tank with a regular sized octopus and models, while the image of the octopus's head half out of the water as it races towards its next victims is pretty cheesy. But, to be honest, the special effects in Jaws really don't look all that special nowadays either.
So it's a rip-off, but so what?
Whether the same can be said for the producer-director's Piranha II, as a sequel to a knock-off, is another matter...