The Final Wish could be the last straw. It’s another example of dumb horror: derivative, factory-product, unscary movie-making that jumbles up a bunch of secondhand tropes without any real storytelling discipline, although there is a decent, professional performance here from Lin Shaye as an ageing woman haunted by her past.

Aaron (Michael Welch), a young guy whose life is going nowhere and who thinks of himself as a failure, has to return to his home town on hearing that his dad has died. There is an uneasy reunion with his troubled mother, Kate (Shaye), local girl Lisa (Melissa Bolona) with whom he is still poignantly in love, and a number of school friends and school enemies. But his late father, an antiques dealer, had in his possession a mysterious urn that can grant wishes – which leads to horrible Mephistophelean choices for Aaron.

I’m a sucker for a Monkey’s Paw-type story, something like the brash Wishmaster films of the 90s. But here, fatally, there is no clarity or internal consistency about how these wishes are to be expressed and granted. Does Aaron literally have to say, or think, some phrase such as “I wish” or “I want”? By the end of the drama, when the number of wishes requested becomes very important, the answer would appear to be yes. But earlier, he could apparently (and accidentally) wish for the death of a dog merely by disliking the animal.

Then there is the time-honoured question of wishing for a dead person to be back with us, and all the spine-chilling implications. Are these reanimated corpses the actual people, or just an evil genie impersonating them? Again, there is something very feeble in the answer to this.

A low-budget scarer like this could have worked. The script lets it down.

• The Final Wish is available on digital platforms from 25 May.