Even though fabricated documentaries – dubbed ‘mockumentaries’ – have been around for a while, they  really only garnered mainstream appeal in 2001 with the acclaimed British sit-com The Office starring Ricky Gervais (I’m choosing to ignore Spinal Tap for arguments sake).  Success struck again in 2006 with Borat, Sacha Baron Cohen’s crude dissertation of American culture, and the hilarious Australian mock-doc Kenny, which followed around a plumber as he installed portable toilets. But note that each of these examples, like nearly all mockumentaries, double as comedies. This is why director Joel Anderson’s feature debut Lake Mungo is such an inspired piece of filmmaking. Not only is it a mockumentary, but it’s also a horror film, and a damn effective one at that.

Credibly told via an assortment of talking heads, Lake Mungo recounts the drowning of troubled sixteen year-old Alice Palmer (Talia Zucker) in a dam near Ararat, Victoria. Whilst her body is positively identified by police, Alice’s parents, Russell and June (David Pledger and Rosie Traynor), and younger brother, Matthew (Martin Sharpe), are convinced her ghostly presence still lingers in their house.

Weeks after her death, photos of Alice standing eerily in the background turn up, prompting Matthew to set up a constant video camera in their living room. When it captures a figure moving about the house one night, the Palmers call up the help of radio psychic Ray (Steve Jodell), who helps the family uncover the reason for Alice’s ghostly presence and the significance of Lake Mungo, a dried up lake where she camped a few months before her death.

Every time this slow-burning thriller appears to be running out of wick, Anderson’s screenplay drops in an unexpected twist with impeccable timing. There’s a lot more to this ghost story than what first meets the eye, and its steady drip-fed method of storytelling, delivered via an entire cast of natural performances, makes captivating use of its 90 minute running time.

It’s somewhat remarkable the film is as engaging and atmospheric as it is considering there isn’t all that much action or drama, given most of the film consists of interviews, snippets of grainy video footage and a number of  blurry photos.  But what’s even more remarkable is that Anderson delivers genuine chills with next to no gore, few jump scares and all on a meagre budget. As such, Lake Mungo is essentially the antithesis of a typical Hollywood horror, and yet it works far more effectively than most. Why? Because it feels genuine.

A common problem I have with horror films is that, no matter how convincing the script and performances are, I’m always conscious of the fact that the characters are standing in front of a meticulously placed camera. It’s not nearly as frightening when you’re aware of the fact that behind said camera, a dozen or more crew members wait in silence. Much like The Blair Witch Project did before it, Lake Mungo has cleverly overcome this notion by making the camera feel a part of the film itself, using amateur handy-cam footage to unnerving effect. Even when cinematographer John Brawley does utilise traditional 35mm film, such as during the interview sequences, the film retains an eerie sense of reality through its convincing documentary structure. It’s all expertly underpinned by David Paterson’s brooding soundtrack, which further helps make Lake Mungo one of the most compelling and suspenseful horrors to emerge in recent years.

Lake Mungo opens across Australia on July 30th.

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