After the mammoth, astonishing success of Jurassic World, there's now considerable proof that nostalgia is box office gold - if you couple it with a viable, relevant movie star. While Terminator first hit cinemas in the 80s, it was its seminal 1991 sequel, 'T2: Judgement Day' that really resonated with audiences and cemented Arnie's robot as an iconic cinematic figure.

This is now the third time (in movie form) that they've attempted to catch that James Cameron-infused lightening in a bottle and the third time they've failed. Despite some fun Arnie moments, Terminator Genisys is a convoluted blockbuster that feels disconcertingly flat.

Starting off with promise after a bit of back story (er, in the future), an aging Terminator affectionately known as 'Pop' by Sarah Conner (Clarke) is the sole protector of the woman who will bear the offspring that ultimately saves the human race; well, until Kyle Reece (Courtney) turns up having been sent back to 1984 by John Conner (Jason Clarke) to protect his Ma (and knock her up... with him).

Yep, it's multiple timelines ahoy here, with 'Salvation' completely ignored, as the franchise reaches its second, third and fifth set of actors playing the same roles - sans Arnie who's been a relative mainstay.

The rights for the Terminator films are split all over the shop, meaning different studios and producers own the copyright for some things that the producers of Genisys/Salvation etc. weren't allowed to use. Taken in that context, Thor 2 director Taylor does a solid job of occasionally making this feel like an actual Terminator film. Granted, the presence of its original star helps, but a script that has too much exposition to deal with fails the characters as a whole.

Sure, 'Pops' has some amusing moments and his first scene (coupled with the iconic Terminator score) genuinely makes the hair on the back of your neck stand up. The problem is, it feels like a film built around that scene, with too much time spent plugging too many holes elsewhere.

Even at the most rudimental level it could work if the action was well staged and the character sparks were there. But we've already seen San Francisco destroyed on screen this summer, and Taylor's grasp of the set pieces is more frantic than fluid - he does nail the more comedic moments though. As for the relationship between Sarah and Kyle, this is where the movie really struggles; Courtney doesn't have much to work with but his performance still lacks a certain edge and urgency. Clarke does her best and has strong potential as a leading lady, but this isn't the vehicle to showcase it, despite the scale.

Also, a glorified JK Simmons cameo just makes you want to see more of him after an initially intriguing introduction turns out to be meaningless.

If this franchise is to continue, it needs a new director with a clear vision from the start - not a helmer for hire. But that's been the problem with three sequels now.