The proper definition of “indie cinema” has been the buzz debate at The Times BFI 52nd London Film Festival. Once upon a time these two noble words heralded an experimental director in charge of his destiny. Now the phrase is Hollywood shorthand for a $10 million to $20 million studio drama with an Oscar-nominated performance and a serious box-office campaign.

Last week I pitched up at the NFT for a seminar called Indiewood is Dead . . . Long Live the New, True Indies, featuring five young American film-makers. It was almost impossible not to cheer. American indie directors still lead the way. They have an innate ability to pick up a camera as naturally as we would a book. This generation of thirtysomethings has absolutely no cash, but it does have a militant desire to make the next great film, come hell or high water.

Their simple-looking dramas are surprisingly sophisticated. Ramin Bahrani’s Goodbye Solo is a gripping and dusty fable about a Senegalese taxi driver who picks up a granite-faced drifter in North Carolina. Joe Swanberg’s improvised drama, Nights and Weekends, explores the agony of a long-distance love affair in Chicago. And Azazel Jacobs casts his own parents in Momma’s Man, an original comedy about a slob who hasn’t got the guts to leave home.

Ironically, many of this generation of American film-makers still scrape a living waiting tables to fund their work. But what’s interesting is how quickly they are cooling towards festivals such as Sundance. Robert Redford’s annual bash is considered far too mainstream for the sort of fresh work that features in the LFF’s Experimenta strand. Directors such as Swanberg are congregating elsewhere: notably London, and even music festivals such as South by Southwest

They are also starting to adopt the attitude and survival tricks of indie pop bands. “The lifestyle of underground rock bands is almost identical to that of indie film-makers” Swanberg says. “Bands grow their own audiences. That’s what film-makers have to do.”

The profound gap between the slick red-carpet galas in Leicester Square and the raw experiments on the fringes of the festival has always fascinated me. I’ve rarely enjoyed so many walks on the wild side. Here are some exceptional indie loners that really stood out.

Tony Manero — Pablo Larraín’s dark thriller about a 52-year-old loser called Raúl Peralta (Alfredo Castro) who becomes infatuated with the spivvy dancer played by John Travolta in Saturday Night Fever — is a beastly good film. You sense just how unhinged Peralta really is when he takes his rented disco suit to the umpteenth matinee screening of the film in a fleapit in the backstreets of Santiago. This is Chile in 1978. Pinochet’s secret police are at their vicious and unpredictable worst. Psychopaths such as Peralta, who will kill for a television set, melt into the humdrum background. This is what makes the film such an unnerving and awful pleasure.

Anthony Haney-Jardine’s religious trilogy of short stories, Anywhere USA, is an utterly potty joy. In part one, a couple of happily married trailer trash hippies are torn apart when a paranoid dwarf in the next caravan becomes convinced that Tammy is turning into an Arab terrorist. In part two, a young girl drinks a bottle of whisky and pulls a tooth out with a pair of pliers to see if the Tooth Fairy really exists. In part three, a retired, middle-aged golfing bore has an orgasmic and guilty urge to bond with a black person. This is an absurd, delightful, and surprisingly gentle satire.

It’s hard to know where to place a film such as Morgan Dews’ shocking Must Read After My Death. The LFF has always had a powerful interest in biography, specifically personal histories recorded on home-made tapes and old film footage.

After the death of his grandmother, Allis, in 2001, the film-maker Morgan Dews discovered a treasure chest of Super 8 home movies and tapes recorded during the 1950s and 1960s. The story of this sad, dysfunctional family is told in their own words. Allis and her philandering husband, Charley, use the tape deck as a confessional and encourage their damaged children to do the same.

There are years of lonely diary entries. Some of the most heart-rendering footnotes concern Dr Lenn, the therapist who wrongly condemned one of Allis’s sons to a mental institution. The other three children are not far behind. The evocative images of happy family get-togethers, captured so beautifully on-camera, chime horribly with the bottled grief we hear down the years. This is extraordinary cinema; and a powerful antidote to the gala glamour.

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