Paranormal Activity 3

Having mercifully conquered the Saw franchise in a David and Goliath-style box office battle over the last two Halloweens, Paranormal Activity returns to take us back to the root of the disturbance. Ironically, the series threatens to follow in the Saw films' footsteps by diluting itself and tarnishing the goodwill built up by what has gone before through slavish adherence to a previously successful formula. Despite drafting in new directorial blood in the form of Catfish creators Ariel Schulman and Henry Joost, it's unfortunately more a case of the law of diminishing returns than 'if it ain't broke, don't fix it'.

Katie and Kristi seem to be happy and carefree children, with a loving mother and a step-dad they both adore. Like many kids, Kristi has an imaginary friend, whose presence is initially seen as normal by Julie and even cute by Dennis. As the invisible playmate's influence grows more unsettling, Dennis decides to use his film-making expertise to try to capture Kristi's interactions with 'Toby'. The extent of the entity's power initially has him excited as a fascinating and potentially lucrative discovery, but when the spirit starts to increasingly threaten Katie and everyone else in its path, the family come to realise they may be messing with something way beyond their understanding.

This new entry again offers subtle departures from its predecessor, with the Trash Humpers-echoing VHS aesthetic and limitations of the Eighties technology leading to a few fresh situations and some obligatory ingenuity on the characters' parts. The period detail isn't as imaginatively employed as it could have been though; apart from a crowd-pleasing cameo by Teddy Ruxpin and the lack of mobile phones, you'd be hard pushed to tell this wasn't the modern day, the dialogue tragically failing to echo the decade's lingo.

On the plus side, the house is more of an architectural nightmare than the previous films' locations, leading to some effective instances of out-of-shot horror and inducing a more powerful paranoia from the increased necessity to scan the screen. Also, the script follows the second instalment's example by taking an impressively mature and realistic approach to portraying an unconventional family dynamic; of course the sisters would love their new step-dad, the young and fun Dennis un-stereotypically embracing his responsibility and becoming a powerful, positive presence in the three girls' lives.

However, character development goes out of the window (along with Julie's character) and dramatic potential is squandered once the film's set-piece structure kicks in; ridiculously, recording the events becomes more important than the events themselves. It's hard to care about the adults when they are so blind to their children's welfare, Dennis instigating and provoking the demonic attacks while Julie dismisses his alerts out of hand.

The situations grow ever more contrived, and credulity is strained by the occasional interlopers' reactions to some particularly distressing encounters either being glossed over by the film-makers or ignored by the other characters. Like the similarly mounted but more traditionally directed Insidious, the script takes a gamble by changing tack and setting towards the end; this functions as a false sense of security-instilling moment of respite as well as providing some expanded potential for subsequent scares, but it also sacrifices any sustained atmosphere and feels a little stretched.

The acting is better than it was in the original but sadly not as strong as it was in Paranormal Activity 2, a fact illustrated by the unnecessary prologue (a further prequel to the second film) where Katie gives heavily-pregnant Kristi a box of the home movies we're about to endure. These short scenes highlight again how much more accomplished the sequel's Sprague Grayden is as an actress than the original's Katie Featherston; they also set a template for the inconsistent performances this new film is burdened with.

Lauren Bittner should have been given more to do; she's easily the most nuanced actor here, but is relegated to the background for most of the duration despite being the character who should be most afflicted by her daughters' plight. Christopher Nicholas Smith is bizarrely reminiscent of the original's Micah Sloat, and just about as sufferable; he fares pretty well in under-played moments of affection, but he doesn't have the charm for the audience to forgive his character's frankly dumb naivety. Jessica Tyler Brown is appropriately freaky and vulnerably innocent as young Kristi, but Chloe Csengery fares less well as her older sister Katie, the script more or less reducing her to an easy target for repeated terrorisation.

The first film took obvious and understandable inspiration from legendary BBC mock-doc Ghostwatch and found footage pioneer The Blair Witch Project, while the second aped Spanish zombie shocker [Rec]'s ending for its own climax. This new prequel riffs shamelessly - and perhaps appropriately given the Eighties setting - on Poltergeist; dope-smoking, naughty-talking parents, the presence-declaring earthquake, kitchen furniture shifting off-screen. It's all a little too familiar when combined with the by-now yawn-inducing format.

As the attacks grow more elaborate, the victims continue to ignore the danger they're in; it's just about believable that they don't want to exacerbate the problem by showing how much it's affecting them - a sentiment the girls communicate more convincingly than the adults - but such a frightening physical force would surely have them running for their lives. The frantic finale takes the action into an unexpected occult dimension, but the initial excitement these scenes generate is dissipated by Dennis' on-going, inexplicable attachment to his camera, while anyone who's seen The Last Exorcism will feel short-changed by the ending, and not only because it's similarly abrupt and cheaply ambiguous.

The final revelations make next to no sense in the context of the previously established storyline; surely the girls would remember some of these events or question what happened to them and their family? Ultimately, this prequel muddies the mythology rather than deepening it; it's hard to see where the series can go from here, but a true sequel to the second (and therefore the first) film should be the only logical progression.

There are a handful of genuinely inventive moments here featuring playful but frightening supernatural occurrences - just don't go expecting anything you've seen in trailers to actually happen in the final film - but when the fuss has died down and the over-hyped audiences have stopped shrieking, Paranormal Activity 3 will be seen as nothing more than a moderately effective string of noise-enhanced jolts. It's a disappointing development for a series that looked to be on the ascendancy, the bigger budget and increased use of CGI only taking some of the edge off the all-important illusion; hopefully Oren Peli can steer his creation back on course in time for next October's inevitable fourth instalment.