Anyone who's ever had to endure more than a 30 minute stretch on Britain's motorways will sympathise with the fact that each and every journey feels like a living purgatory.
Locke takes that to its narrative conclusion, crafting an 85 minute emotional drama that takes place almost solely within the confines of a car, the man driving it, and a three hour-long journey in which all conceivable emotional hell breaks loose.
If that sounds a little too monotonous or high concept, then know that the man in question, Ivan Locke, is played by none other than Tom Hardy, who manages to make the tale riveting and magnetic, despite the occasional scripting wobble.
Boasting a Welsh accent, a gruff beard and the resigned aura of a man fully aware of the inevitable trudge towards a life-enveloping emotional implosion, he anchors the story in which Ivan's personal and professional lives are both on the precipice of disaster.
Confined to his car on a desperate drive to London, he takes and makes call after call in a spiralling narrative that draws in his wife, children, boss, former colleague, a spattering of side characters, and a whole host of Daddy/morality issues.
While the supporting roles (or voices) are always engaging (helped by a semi-starry cast including Olivia Coleman, Alice Lowe, and The Lone Range r 's Ruth Wilson), some end up more grating than gripping, so it's lucky that Hardy is on top form, with an emotionally fragile and dense performance that resonates as the heart-aching tether.
Part Buried and part Drive , but more dramatically grounded (no hammer bludgeoning or stuck in a coffin-ing here), it's a claustrophobic, emotionally weathering and yet always watchable ride.
For more Sundance movies, check out our list of the 30 Movies We're Most Excited About at Sundance 2014 .