Perhaps it’s not a strange coincidence that this week brings two films about the precious commodity that is water. (The other is The Source.) More than oil, more than land, certainly more than ideology, one day the thing mankind will fight over is access to the element without which life is unsustainable. Written by Ken Loach's sometime scriptwriter Paul Laverty, Even the Rain is an impeccably liberal study of ownership of the water supply that doubles as a parable about modern imperialism.

Welcome to our second show, brought to you again from the Red Bull Studio in London where it was recorded by Brendon Harding.

Richly nuanced in its sideshot view of Uruguay’s film world and Montevideo street atmosphere, Federico Veiroj’s A Useful Life is a small film that picks up on suppressed emotions which are only released in its second half. Its black-and-white images (actually transferred from colour, in a manner consciously evoking previous eras) recalls something of European cinema of the 1950s and 1960s. The three non-professional leads live rather than play their parts, but it’s atmosphere, conveyed especially through its score, that gives the film its charm.

In later years, when callow reporters would be sent to interview the wrecked legend Hunter S Thompson in his Colorado compound, at some point in the weekend, in between the drugs, booze and random gunfire that punctuated his days, the Gonzo journalist would betray unaccustomed nerves, and point his guest to a pile of typewritten pages. This was The Rum Diary, an attempted novel from the early Sixties he picked at for four decades.

At the newly renamed Harold Pinter Theatre (formerly the Comedy), the inaugural show is a special tribute to the Nobel Prize-winning playwright, who died in 2008. The subject matter of Ariel Dorfman’s play, which won an Olivier Award on its first outing in 1991, is a powerful reminder that Pinter was a human rights activist. He was also a friend of Dorfman so this revival, which stars Thandie Newton and opened last night, is an inspired choice of production.

Post Mortem is Chilean Pablo Larraín’s follow-up to the extraordinary Tony Manero, and another, even tougher take on his country’s troubled past. While the first film was a blackly comic look at the dictatorship years of the Seventies, this one deals with the coup itself. It’s a harrowing experience, but one that confirms Larrain as a major talent.

On 5 August last year, a cave-in at Chile's 121-year-old San José copper mine left 33 workers trapped more than 2,000ft underground. Their subterranean ordeal would last 69 days, but this documentary concerned itself with the first 17 of those, the period during which the miners had no contact with anybody on the surface and had no way of knowing if they'd be rescued.

Perhaps I’m being too literal-minded, but demanding South American music from a concert programme advertised as “South American Baroque” doesn’t seem entirely unreasonable. When you add Colombian-born soprano Juanita Lascarro as soloist and Brazilian Rodolfo Richter as leader it seems actively desirable – a chance to encounter an underexposed seam of music in the hands of expert guides. Turns out that all musical roads lead back to Europe, to the ubiquitous Scarlattis, Handel and Hasse, and despite a few exotic excursions to the New World it was in the familiar Old that we spent the bulk of our evening.

The thin line between Art and Craft gets slimmer as artists like Carlos Zuniga ignore the borders and delve into hands-on production processes. This Chilean photographer, architect and graphic designer works compulsively on large, imposing portraits and landscapes using intensely obsessive techniques.

For 15 years after the death of his demon muse Klaus Kinski, Werner Herzog made documentaries about equally obsessive visionaries, climaxing five years ago with Grizzly Man’s tale of Timothy Treadwell, who loved and was eaten by bears. Though the documentaries continue, Herzog is now finally re-engaging with feature films. My Son, My Son, What Have Ye Done was made back-to-back with Bad Lieutenant and shares some of its cast.