By David Kettle

Mexican director Alejandro Molina’s quiet, thoughtful feature feels somewhat like a throwback to classic science fiction – there are elements of Logan’s Run, Brave New World, even Nineteen Eighty-Four. But though its themes might seem familiar, it establishes an absorbing atmosphere all of its own, and its stylish design, stunning cinematography and subtle, elusive themes take it a notch above the usual sci-fi fare.

Molina imagines a future where overpopulation has become so intense that the government implants an enzyme into each person’s DNA to regulate their waking and sleeping hours, thereby dividing the population into day-time and night-time citizens who never meet – all watched over by the sinister Leaders, whose word is law.

Two humans’ lives intersect through the discovery of a child whose time period has been mysteriously switched from day to night, and the trio form an unlikely family unit. There’s the complication, however, that although the mother (a restrained performance from Sandra Echverría) is awake during the daytime, the father (a fragile Manuel Balbi) can only function at night. Nevertheless, they begin to question the rules they have been brought up under and plan their escape.

The slow-moving pace and lingering shots provide plenty of time for viewers to contemplate the film’s themes, and the extended coda – a demanding yet meditative 20 minutes without dialogue – moves the work from narrative into pure visual poetry. It seems only appropriate that it’s an eclipse that finally brings the lovers together – briefly.

With its subtle colour palette of blues and greys, and its understated yet resonant performances, Molina’s highly poetic, philosophical take on science fiction lingers long in the memory.

By Day and By Night (De día y de noche); Spanish dialogue with English subtitles; Mexico, 2010; 90min