In the opening shot of Son of a Lion, an 11-year-old boy points a 9mm handgun directly at the camera. Thus Benjamin Gilmour introduces us to Niaz, the young Pashtun from the town of Darra Adam Khel in Pakistan’s Northwest province at the centre of this revealing growing-pains tale. Working for his widowed father, an ex-Mujahideen who runs one of Darra Adam Khel’s many weaponry workshops, Niaz’s boyhood has been spent among the guns that are his father’s trade – and an integral part of Pashtun tribal culture. But chafing against his father’s strict upbringing, Niaz wants desperately to go to school, where he hopes to pursue an interest in the music of which his dad disapproves.

Having developed his screenplay in collaboration with his local cast, Gilmour – an Australian – provides an extraordinarily rich picture of this remote, proudly independent community. From the vivid glimpse of Darra Adam Khel’s many gun shops, whose exteriors are painted in gaudy colours advertising their wares, to the noisy excitement of a cinema in Peshawar, Gilmour’s observant camera captures the everyday atmosphere of a part of the world most commonly portrayed in sensationalist news reports. It’s a culture of flinty austerities, shot through with plenty of moments of dry humour: a jocular description of his beard as an “Al Qaeda” made by Niaz’s father in his local barbershop suggests he and his fellow Pashtuns can still crack the odd joke about the ongoing war on terror.

But it’s in the more intimate story of Niaz’s coming-of-age that the film is most compelling. Niaz, played with a mix of guileless charm and piercing vulnerability by Niaz Khun Shinwari, is movingly torn between loyalty to his father and his own desires. In one scene a group of tribal elders despair of the way they are stereotyped by western film-makers. Gilmour answers their complaint with this film, an affecting study of Niaz, a dreamy kid unsure about his future and with a difficult relationship with his dad. In other words, he’s just like any other adolescent.