When both towers of the World Trade Center came crashing down on 9/11, it sent ripples of shock and fear around the world. It was such a blatant attack on democracy, that the US demanded not only answers, but revenge.

As a direct result of the attacks, the US built a detention centre on the coast of Cuba, at Guantanamo Bay. It is here that Mohamedou Ould Slahi found himself incarcerated for the crime of being the recruiter for those terrorists on board the planes. Kevin McDonald’s latest film, based on Slahi’s 2015 memoir, is a thought-provoking examinination of US justice, and how severely unjust it can be.

Having been awarded a scholarship to study in Germany, Mohamedou Slahi (Tahar Rahim) finds time to return to his home of Mauritania, West Africa, to see family and friends. Acting on Intel they have, the US government swoop in and take him in custody.

Slahi finds himself in the infamous Guantanamo Bay detention center, where it’s hoped he will admit to his part in 9/11, one way or another.

His case lands on the desk of defense attorney Nancy Hollander (Jodie Foster), who decides to represent him, particularly as the US government had yet to charge him for any of the crimes accused of him.

She knows she’s up against it though, especially when the formidable Lt. Colonel Stuart Couch (Benedict Cumberbatch) is appointed the military prosecutor. Couch expects a fair fight, and is keen to prosecuted if indeed guilty, but begins to feel the case may not be as clear cut as it’s made out to be, when even he is faced with obstacles when requesting legal documents from the US military, despite being on the same side.

When a script based on such a fascinating story lands in the lap of a director, he must rub his hands with glee. Audiences should do the same when said script lands in the highly talented lap of director of Kevin Macdonald, whose vision for such a story is sublime.

To be fair, the story does most of the heavy lifting, retelling a story so remarkable, it feels it should have been told a lot sooner. But Macdonald then casts some heavy hitters in Rahim, Foster and Cumberbatch, who all manage to elevate the material to another level. Rahim in particular is exceptional, in what could easily be a career-defining role; his performance is truly magnificent, as he conveys the sense of a man being broken physically and mentally over the years. Indeed, never has an actor emoted so convincingly with his eyes before, reflecting the sheer futility of his situation.

Of course Macdonald, with such a great cast and thrilling story, could have just delivered an almost painting by numbers true life drama, and he would have gotten away with it. But his direction not only gives it added pathos, he keeps audiences both glued and gripped throughout, with an impressive end that certainly deserves a special mention.

The Mauritanian is one of those stories that feels too unbelievable to be true, and yet it is another title to be added the growing list of US injustice that already exists. With such an impressive cast, Macdonald turns something that could easily have been fairly humdrum, into something haunting, riveting and utterly absorbing.