Marshland

The twisted landscape of the Guadalquivir wetlands - seen first from above, its inlets and waterways sprawling so that it resembles nothing so much as a human brain - is matched by the sociopolitical intricacies of smalltown Spain of 1980, where the vestiges of the Franco dictatorship and the emerging democracy run like rivulets into one another jostling for dominance. An early reference to "Your new country" and the sight of a crucifix on a hotel wall featuring cut out photos of Hitler and Franco are further evidence of a nation in flux.

Alberto Rodríguez and co-writer Rafael Cobos understand the art of noir insinuation, scattering hints of malaise and suggestions of threat casually across the landscape, as their two police anti-heroes arrive like aliens from a distant star. In fact, the pair have only come from Madrid, called to investigate the disappearance of two teenage sisters, but as far as the locals are concerned they pose almost as much of a threat as the possible killer in their midst. The cops eye one another with almost as much suspicion as the populace they've come to help. Pedro (Raúl Arévalo) is young and wet behind the ears while Juan (Javier Gutiérrez, who won the best actor award at San Sebastian) is hardened and old school, representing the fallen regime and resistant to a new era.

Tensions sing through the narrative as first the teenager's coiled-spring father (Antonio de la Torre, who always makes his presence felt) and, in all probability, abused mother (Nerea Barros) enter the equation, the latter clutching half-burnt photos of her daughter in a compromising position. Then a drunken gunman arrives at their hotel soaked in alcohol and sorrow over another sinister incident from the past. Other distinctive characters - again representing a complex mix of old and new - flit through the landscape. They include the young, swaggering Quini (Jesus Castro), who feels more like a product of his country's past than a hope for its future and a deadbeat journalist (Manolo Solo), who acts as a historical conscience at the same time as making unconscionable requests.

Heat and oppression hang in the air like an unspoken accusation, with cinematographer Alex Catalan - whose work is impeccable throughout - using magic hour shots of the raw natural beauty of the wetland marshes to underline the claustrophobia of a town filled with deep mistrust and social unrest. This is also a place drowning in the worst aspects of unreformed masculinity - women are missing or too scared to speak, while the promise of a better life for them holds hidden peril.

While some of the basic story aspects may be familiar, the grit of the narrative gives it weight, and as we learn some of the secrets of the town, they arrive less as revelations than as grimly stitched pieces of a troubled community tapestry. The murder mystery is intriguing and intricately worked within this backdrop but this is as much a film about the murky history of Spain and the difficulty in shaking it off as it is about the murders. Compromised morals may bring results but they also muddy the distinction between the saint and the sinner and suggest that the road ahead is boggy at best.