After celebrating her admittance to MIT, high school student Rhoda Williams drives home while listening to a radio broadcast that reveals another planet has been found in our solar system. Drunk, and staring up into the night sky to catch a glimpse of the distant blue dot that is this new world, Rhoda fails to notice another car stopped at an intersection and crashes into it at high speed. Only she and the driver of the other car, a composer named John Burroughs, survive; his wife and young son are both killed instantly.

Several years later Rhoda is released from jail. By now the new planet has been identified as a mirror Earth – a parallel world to our own – and looms large in the sky both day and night. With her life irrevocably changed by the events of that fateful night years before, Rhoda’s ambitions fall by the wayside and she instead takes a job cleaning at a local school. She is, however, compelled one day to visit Burroughs at his home with the intention of apologising for her actions. But when confronted with the man whose life she destroyed Rhoda cannot bring herself to admit the truth and instead finds herself offering her services as a cleaner. As she was a minor when the accident happened, Burroughs is unaware that she is responsible for the death of his wife and child and accepts her offer.

The debut feature from award-winning documentary maker Mike Cahill is an accomplished film that is neither science fiction nor a love story. Instead it’s a film about one person’s search for redemption, and it tells this story very well. The idea of parallel worlds is one that has long existed in science fiction, yet Another Earth doesn’t explore the concept in any significant detail; instead it uses the notion of a second planet like our own as a way to bring Rhoda and John together and explore how they have dealt with a moment in time that changed the course of both their lives forever. One scene in particular shows both characters sharing their feelings about the mysterious planet to one another; while Rhoda looks upon it as offering a second chance, an escape from the life she has lost and the life that she stole from John, he is almost fearful of it, insistent that it should not be explored. Despite his concerns a competition to win a trip to the parallel world thus assumes great significance for Rhoda.

As befitting Cahill’s previous work the film is shot in a style reminiscent of a documentary, which helps to bring a more visceral feel to the film’s more dramatic moments; a scene in which Rhoda’s family watch the instant of first contact with Earth 2 on television, for instance, is a wonderful example of how to raise tension and keep an audience on the edge of their seat through a combination of good writing and direction.

With a film that so closely examines the relationship between two people such as this, Another Earth’s success hinges on the performance of its two lead actors, Brit Marling as Rhoda and William Mapother as John, a responsibility they carry brilliantly. Marling, who also co-wrote and produced the film, puts in a tremendously understated performance that allows Rhoda to gain the audience’s sympathies despite her actions at the beginning of the story. Mapother, meanwhile, is utterly convincing as a man whose life has been put on hold since the death of his family. The developing relationship between the pair, from their very first encounter when Rhoda arrives on John’s doorstep, has a natural feel to it that adds to the sense of realism that is present throughout, despite constant reminders that a parallel Earth is hanging in the sky above them.

Elsewhere, the addition of astrophysicist Dr. Richard Berendzen as a narrator lends an authoritative tone to the otherwise fantastic possibility of a world that mirrors our own, helping to ground the concept in a degree of reality however slight it may be.

Approach Another Earth as a movie concerned exclusively with the idea of a parallel Earth and you will be disappointed. Consider it instead as a character piece focusing on two people whose lives are brought together as the result of a terrible accident and you’ll find it to be a powerful, emotional indie drama and a thought-provoking film that remains with you long after the credits roll.