Here is a squawking, gobbling, factory-farmed turkey, and it’s a shame because its co-creators Justin Benson and Aaron Moorhead are a film-making duo known for interesting sci-fi horror fantasy. In 2017, they gave us a very intriguing indie movie called The Endless, in which they also starred as two thirtysomething brothers who 10 years previously had been freed from a sinister cult, but make a strange decision to revisit this creepy brotherhood whose world now seems more interesting than their current banal existence.

That was a very atmospheric, if confused film. Sadly, all the problems with it seem to have magnified for this muddled and exasperatingly slow and pointless drama. Anthony Mackie and Jamie Dornan play Steve and Dennis, two careworn paramedics in New Orleans having to deal with the casualties of a new synthetic drug called Synchronic with time-travel powers. The problem with “imaginary drug” films is that they’re an easy and unearned route to excitement, and only a very rigorously clear and consistent narrative, and preferably a humorous script, can make them work. Ariel Schulman and Henry Joost’s Project Power (2020) was another imaginary-street-drug-in-New-Orleans film that was successful because of bright performances from a cast headed by Jamie Foxx. Similarly, Neil Burger’s Limitless (2011), with Bradley Cooper’s washed-up loser getting a mega-IQ boost from a brain pill, was viable as raucous satire.

But Synchronic is frankly just silly and tedious, with faintly absurd and jeopardy-free time-travel scenes and a dramatic focus hopelessly split between Dennis and Steve’s separate but equally tiresome lives. There is a laugh when Mackie’s exhausted time-traveller comes back to the present and declares to his video diary: “The past fuckin’ sucks, man.” As does so much else.

• Synchronic is available on digital platforms from 29 January.