When Jaws was an unprecedented commercial success in 1975, it inspired every enterprising independent producer to make their own version to profit from the original’s success. I recently watched Michael Anderson’s 1977 film Orca, likely the most successful and well-remembered of these derivative works. That film has maintained a reputation as the poster child for knock-off movies, but it turns out there several other attempts that selected their own voracious animal threats. Joe Dante’s Piranha (1978), Lewis Teague’s Alligator (1980), and even William Girdler’s Grizzly (1976) each took their chance only to linger on as home video fodder in the early 1980s. I think I have identified the worst example of this craze, and it is Ovidio G. Assontis’ 1977 film Tentacles – in which an American seaside town is menaced by a giant angry octopus. As Jaws‘ Mayor Vaughn might say, ‘you yell “barracuda”, everybody says “huh? what?” You yell ‘octopus’… everybody probably still says ‘huh? what?’

This is an odd film, and while it is impossible to recommend on quality grounds it does feature some bizarre creative choices that at least turn it into a mild curiosity. One of them is the casting. Tentacles features a maverick local journalist who investigates a series of deaths in the ocean. He determines whatever animal is killing people has been unsettled by undersea tunnel work done at the behest of an ambitious property magnate. With resistance from both the millionaire property builder and the local police, soon everybody in the water is at risk of octopus attack – including the young son of the journalist’s sister.

The maverick journalist Ned Turner, who effectively adopts the equivalent role to Jaws‘ Sheriff Brody, is played by 71-year-old John Huston. He was a great actor, and an even better director, but he is shockingly miscast here. There is no energy to his performance. In a crisis he cannot run to get help; the best he can manage physically is a halting sort of jog. In one early scene he is depicted getting out of bed, and he is dressed in a floor length 19th-century nightshirt. That he is a solid 30 years too old for the role is not just ignored – it is actively exacerbated.

Weirder than that is the casting of Turner’s sister Tillie, in which 57-year-old Shelley Winters plays mother to a child who can be all of ten years old. While not inconceivable, it simply fails to be convincing. Neither does the brother-sister relationship between Tillie and Ned, which is some scenes feels disturbingly inappropriate. More suitable is the casting of Henry Fonda as property developer Mr Whitehead, although it is painfully apparently he shot all of his scenes in a backyard shouting into a telephone. With that much aging star power, the budget can only stretch so far.

The pace of the film is unforgivably slow. With a b-grade cash-in, the viewer should at least be able to expect some garish action and fish-on-human violence, but Tentacles takes an absolute age to get going. The climax is silly – two trained orca and their handlers versus an enraged octopus – and underwhelming. Really the only sequence to show any sense of energy or momentum is a yacht race that is interrupted by an octo-rampage – and that is in part due to Stelvio Cipriani’s superb electronic score. Really it is the only part of the film worthy of praise.

Even the title is a mockery, since octopuses don’t even have tentacles – that would be squid.

Tentacles is currently streaming on Amazon Prime. You lucky people.