The spoils of war are a chore in this fascinating fly-on-the-wall study of the Taliban’s first year in power. Ibrahim Nash’at’s documentary is named for its principal location, a former CIA stronghold on the outskirts of Kabul, hastily abandoned and haphazardly vandalised by its previous tenants. The base contains treasures but it has been left in a state. Afghan fighters pick their way through the corridors, weighing up their surroundings, wondering just where to begin. They could be a band of hotel cleaners called in to mop up after a heavy-duty stag weekend. Leading the band is Mawlawi Mansour, a bushy-bearded Taliban commander whose father was killed in a US airstrike. Nash’at shows him doggedly going about his duties. He stretches his legs on the newfangled treadmill in the gym. He checks the expiration date of cough drops and calamine lotion in the medical stockroom. “Our head doctor is lazy,” one of his lieutenants explains, at which point Mansour flashes a pained look at the camera. The commander likes to boast that his own wife was a doctor before giving up work as a condition of marriage. If Mrs Mansour was still free to practise, she might have been able to lick this small hospital into shape. Nash’at – who was born in Egypt and is based in Berlin – spent 12 months trailing Mansour and his crew, loitering in the background and shooting from the sidelines. If his finished film is light on probing interviews and rigorous analysis, there’s an obvious reason: his subjects all hate him. The Taliban fighters view every journalist as a foreign spy and have accepted the presence of this one only under duress. “That little devil is filming again,” one mutters when Nash’at draws too close. If the director misbehaves, says another, he will promptly be taken outside and killed. When US forces quit Afghanistan in the spring of 2021 they left behind an estimated $7bn (£5.5bn) worth of military equipment. Mansour’s main task – in addition to checking expiration dates – is to oversee the repair and repainting of the fighter jets and Black Hawk helicopters, officially in advance of a victory parade but also conceivably in preparation for a war against neighbouring Tajikistan. This prospect appears to provide the soldiers with a sense of purpose, something to fill their days and plug the gaps in their hearts. The Taliban are triumphant, but this win feels like a loss. “My burning wish is to see American troops still here,” one soldier admits. “That way I could ambush them, kill them, die and become a martyr.” While it would have been good to have Nash’at properly cross-examine these men, his film’s careful approach pays handsome dividends. Hollywoodate teases back a corner of the curtain to reveal a Taliban regime stitched awkwardly over the bones of US occupation. It shows us the soldiers pining for the caves where they once hid, and mourning the glorious death that has somehow been snatched from their grasp. The film hits its head-spinning crescendo during the surreal celebrations at Bagram airbase, which feature a motorbike parade by “the suicide bombing battalion”, a unit that wouldn’t have been out of place in Chris Morris’s Four Lions. The battalion’s members pass through in some haste, trailing their broken dreams and dashed ambitions. For these men in particular, there has been no happy ending. They ride off into an uncertain future; unfulfilled, still alive.