Much like the Xenomorphs featured throughout the franchise, the alien films have mutated with each entry. And ever since 1992's Alien 3, their quality has been on the slide.

A dim light was shone down a dim tunnel when original director Ridley Scott helmed 2012's re-boot of sorts Prometheus, which was the first instalment in a prequel series. However, despite looking epic, the dominant themes of the origin of man hijacked the film, leaving little room for the scares audiences were really looking for.

Since then Scott has conceded he got it wrong, and decided to redress the balance with this second instalment, by anchoring it more into its monster roots.

On board the colonisation ship Covenant, in hyper sleep, are two thousand colonists, plus a thousand or so human embryos, looking for a new home. After much research, a remote planet known as Origae-6 appears a sure bet, which is the ship's destination.

However, when it is hit by a highly charged shockwave, android Walter (Michael Fassbender), decides to wake the fifteen crew members from sleep to assess the situation. Unfortunately their captain doesn't make it, leaving Oram (Billy Crudup) to step up to the space plate.

While doing some repair jobs to the ship's exterior, Tennessee (Danny McBride) gets some interference in his helmet. When analysed, it appears to be a message, being sent from a planet in close proximity. Studying the planet further, they discover that it actually makes a good candidate for a new home.

Considering how far away Origae-6 still is, Oram makes the executive decision to send an expedition party down to the planet's surface to give it the once over.

Initially it manages to impress, but when a couple of crew members begin to fall ill, it rapidly becomes clear that the planet is already home to some 'thing' else, and it's not waving any welcome flags out any time soon.

It's understandable that Scott wanted to move the franchise on. Particularly with Prometheus, where he thought with so many entries in the series, the original monster was "definitely cooked, with an orange in his mouth" and wanted to move on from that. But after the reaction from fans, he admitted he got it wrong.

Alien Covenant does go some way to being a concession, and righting that wrong. The iconic Xenomorph does explode back onto the scene, which will certainly keep the fans happy. But Scott isn't ready to let go fully of the creation of man; he is still keen to continue to delve into the existence of mankind, particularly with the return of David (also played by Fassbender) from Prometheus. Marooned on the planet, his character is now akin to a robot version of Brando's Kurtz from Apocalypse Now, but with more hair.

It's admirable to attempt a film to contain esoteric themes, as well as be a monster flick, but by not being one thing or another, the film not only struggles with its own identity, but how it also sits in the Alien canon.

Admittedly it can't be easy to come up with a new spin on an alien rocketing out of a body, or jumping on one from a height, but if that's the case, maybe it's simply time to call it a day.

As it stands Alien Covenant is a slightly above average entry in the franchise, with its fair share of jumps and scares. The story is more accessible, told with Scott's imitable visual style, but suffers from mutating a tad too much outside of its dis-comfort zone.