Ethan Hawke plays a Temporal Agent, an otherwise nameless man who, thanks to a device disguised as a violin case, can travel through time. He’s on the trail of a terrorist called the Fizzle Bomber, whose next attack, in 1975 New York, will result in the deaths of thousands of people. The Agent therefore travels back to the era and assumes the guise of a bartender, where a casual conversation with a local barfly leads us to suspect that the Agent may have already found his culprit. But then the barfly’s story leads us further back in time, as he relates the disarmingly poignant story of an orphaned girl, her growing pains, and her brief involvement in a scientific project overseen by an enigmatic man called Robertson (played by the great Noah Taylor). How all these characters are linked is gradually revealed as Predestination unfolds, and it’s impossible to describe the story in much more detail without spoiling it. Ethan Hawke’s as watchable as he always is as the Temporal Agent; he’s one of those actors who seems so casual in front of the camera that it’s easy to overlook just how intelligent and detailed his performances are. A long stretch of the film is devoted to Hawke’s conversation with the customer in the dreary New York Bar, and it’s to Hawke’s credit as an actor – and the Spierigs’ intimate lighting and photography – that it’s one of the most riveting parts of the film. Then there’s Sarah Snook, the Australian actress who plays the ambitious young woman in the flashbacks. Again, it’s difficult to describe her character in too much detail, but her turn here is magnificent; even when the story stretches the bounds of credulity, the honesty and strength of Snook’s performance is never less than captivating. It’s a tiny moment, but one that exemplifies the directors’ ability – even in a quite dialogue-heavy film such as this – to communicate a character’s inner turmoil elegantly and without words. It’s also unusual to find such tenderness in a science fiction film, or patience for that matter: the directors have the confidence in their performers to simply let the lens linger and observe how they react with sadness, wonderment or horror. Predestination is a perplexing film to write about, because it’s a time travel movie in which the time travel and the assorted twists it brings with it are in many ways its least interesting aspects. What is interesting is the world the Spierigs create from Heinlein’s source material; an alternate version of the past that is at once familiar and strange, where fiddling with time has twisted broken, confused characters into a complex tangle with no clear beginning or end. Predestination is out in UK cinemas on the 20th February. Follow our Twitter feed for faster news and bad jokes right here. And be our Facebook chum here.