Have you watched any American indie cinema recently? If so, you might have encountered a cast of pale, socially maladjusted young men clutching acoustic guitars and failing disastrously to engage the opposite sex in slick, flirtatious exchanges. You might have noticed that the word “Um...” figures heavily in the dialogue and that sentences tend to dangle unfinished. Sounds familiar? Welcome to the world of mumblecore.

As a tag for the one of the more intriguing sub-genres in American indie cinema, it doesn’t have the most prepossessing ring to it. But it refers to a collection of young film-makers considered by many to be the heirs to the likes of John Cassavetes, Eric Rohmer and Woody Allen. With its lo-fi aesthetic, gauche sexual tensions and acutely observed naturalism, mumblecore is the socially awkward Emo kid lurking in the corner of the frat party of mainstream American cinema. And as someone for whom the guiding force of most of my teens and twenties was acute, crippling social embarrassment, I love these movies even as they make me squirm with painful recognition.

It was the director Andrew Bujalski, whose third feature Beeswax screens at the festival, who first introduced the “mumblecore” peg, but the term was originally coined by sound editor and Bujalski collaborator Eric Masunaga during the 2005 South By Southwest film festival. Other tags include slackavetes (a pun on film-maker and mumble-hero John Cassavetes), bed-head cinema and Myspace Neo-Realism.

Bujalski appeared in as well as wrote, directed and edited both of his first two films, Funny Ha Ha (a study of a low-key post-college crisis) and Mutual Appreciation (a stumbling love-triangle), and he also acted in Joe Swanberg’s Hannah Takes the Stairs. Meanwhile Swanberg’s latest feature, Alexander the Last, which also screens at the LFF this year, features Bujalski’s Mutual Appreciation co-star Justin Rice. Rice is a member of the indie rock band Bishop Allen which has provided music for several mumble movies; its co-founder Christian Rudder starred in Funny Ha Ha.

Other key mumblecorps are the brothers Mark and Jay Duplass, who wrote and directed the whiney road movie The Puffy Chair and the horror spoof Baghead. Mark Duplass also co-starred in Lynn Shelton’s mumbleporn comedy Humpday. Finally there’s Aaron Katz whose second feature Quiet City featured Swanberg.

Fitting in with a mumblecore audience requires a wardrobe which gives the impression of insouciant devil-may-care anti-styling but in fact is meticulously thought through.

Retro looks should score highly with mumblefans – at the heart of Beeswax is a kitschily chaotic vintage shop.

T-shirts (ironic or otherwise) sporting the logos of obscure indie rock bands should score mumblepoints. For girls, artfully mussed hair, tomboyish vests, jeans and Converse sneakers will achieve that vital androgynous coquette look. Thinly veiled eating disorders are also de rigueur.

Decoding Mumble: a guide

IS THERE A STORY?

Is there conventional framing (can you see what’s going on in a scene)? Does the film end with a climax and a sense that all ends have been neatly tied up? If the answer to any of these questions is yes, you are not watching a mumblecore movie.

Indicators that you have entered mondo-mumble include a micro-budget and cast of bright but directionless recent college graduates drifting into adulthood. Often one of these is likely to be a cool, gamine girl who finds herself drawn to two slightly nerdy but funny guys (see Rachel Clift in Mutual Appreciation; Greta Gerwig in Hannah Takes the Stairs).

The characters bring a new commitment to the term laidback and will probably spend at least 30 per cent of the film horizontal, flirting clumsily with those they probably shouldn’t be.

The impatient might describe it as navel-gazing and even mumble fans would admit that there is a certain solipsistic self-absorption to the characters. But there is also authenticity. These characters feel real, the actors who play them are recognisably human, not the polished alien creatures who populate Hollywood. Their angst is our angst.

WHAT HAPPENS?

It’s tempting to say absolutely nothing but in fact under the gentle ebb and flow of social tensions and meandering conversations are stronger dramatic currents. Take the exquisitely subtle Alexander the Last for example — the niggling passive-aggressive banter between actress Alex and her husband Elliot, the loaded glances she shares with her fellow theatre performer Jamie all speak of the possibility of infidelity, but the real story is the breakdown of Alex’s closest relationship, with her sister Hellen.

Meanwhile in the legal anti-thriller Beeswax, Bujalski refuses to explain a potential court-case that hovers over one of the characters, focusing instead on the anxieties, shared jokes and quirks that tell us so much

about Jeannie, her twin sister Lauren and the way their lives are about to change. Although Jeannie is a wheelchair-bound paraplegic, it is her character and her daily stresses that are the focus of the film, rather than her disability.

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