It’s the near future and Grey Trace is an analog man in a digital world. He works from his garage, fixing classic cars for the rich people who can still afford them.

Meanwhile his wife, Asha, works for Cobolt, one of the big tech companies behind the proliferation of artificial intelligence and robotic augmentations. For not only are cars and homes controlled by computers, but humans are rapidly introducing technology to their bodies too.

Grey’s recently been fixing up a motor for tech billionaire Eron Keen, so the couple drop it off at his extravagant home where Eron shows them his latest invention – STEM – a microchip that promises the next stage in human evolution.

When Asha’s auto-piloted car goes on the fritz and an accident occurs, Grey is paralysed from the neck down and forced to watch his wife get murdered. Unsurprisingly, Eron seizes his chance to get his new microchip tech installed on a broken and willing subject.

Thus Grey, who was sinking into depression, finds himself with a new lease of life, and a desire to hunt and kill anyone involved in his wife’s death. Grey’s new implant provides him with full body movement and more – it even has a voice, and that voice tells Grey exactly how to find his wife’s killers.

Writer/director Leigh Whannell has a lot of fun with the premise, and stretches his meagre budget a considerable distance. The fusing of future tech and old fashioned grittiness is a part of that, the grim, neo-noir setting is easy on the budget and effective on the eye.

And once the movie turns into Death Wish, it finds its stride. However such is the rushed nature of the opening act, the film doesn’t earn the emotional impact it really needs. A brief argumentative exchange between Asha and Grey isn’t enough to sell them as a married couple.

But what follows does work, especially from Logan Marshall-Green as Grey, who not only sells the grief convincingly but also does a sterling job selling the premise for the duration. Particularly once STEM takes control of bodily functions.

This is derivative stuff, one part Death Wish, one part Robocop, with dashings of the AIs seen in Her or even 2001. For a brief moment, it even channels Columbo.

And yet the sum of its derived parts makes quite a substantial whole. The violence arrives in fits and spurts, and is so shocking it’s almost funny, while the plot has one or two twists that most won’t see coming.

The low-key cast helps with that (it’s harder to figure out what’s what when the cast are all unrecognisable), although Harrison Gibertson’s budget Jared Leto performance begins to grate.

Whannell, who cut his teeth writing the Saw franchise (and whose only previous directing credit is Insidious 3), has fashioned an exceedingly good, pulp sci-fi flick that is an equal to the films that inspired it. We shall watch his career with great interest.