Somalia’s Al Shabaab is the most resilient militant Islamist insurgency after the Afghan Taliban. It has proved nimble and adaptable as well as tenacious. It has recovered from blunders, infighting and huge human losses, and remains a formidable presence in Somalia and neighbouring Kenya despite – or perhaps because of – the vast resources devoted to destroying it.

Al Shabaab has a remarkable intelligence apparatus. The title of this book alludes to a phone call that Mary Harper, a BBC journalist and longtime reporter on Somalia, received following a visit to Baidoa in the southwest of the country. The caller was a member of Al Shabaab, who described precisely where she had gone, whom she had met and what she had done in that town, and also in Mogadishu, down to the tube of Pringles she was holding when coming out of a shop. After her itinerary was read back to her, Harper told the caller that everything he had told her was true. She writes, ‘it is ironic that Al Shabaab has been able to describe to me so accurately what I do and whom I see when I visit Somalia while I have found it almost impossible to establish a single certifiable truth about the group.’

Harper is humble and scrupulous. She describes – to be exact, she allows her Somali interlocutors to describe – the different and paradoxical faces of Al Shabaab. It is appallingly brutal and it is everywhere. One of the most telling and disturbing stories in the book recounts how a young