I did almost nothing on my first day as Idi Amin’s doctor. I had just come in from one of the western provinces, where I’d worked in a bush surgery. Kampala, the city seemed like paradise after all that.

Back in my old neighbourhood, I’d seen to Idi once. On his bullying visits to the gum-booted old chiefs out there, he would drive a red Maserati manically down the dirt tracks. Walking in the evenings, under the telegraph poles where the kestrels perched, you could tell where he’d been—the green fringe of grass down the middle of the track would be singed brown by the burning sump of the low-slung car.

On this occasion, he’d hit a cow—some poor smallholder had probably been fattening it up for slaughter—spun the vehicle and been thrown clear, spraining his wrist in the process. The soldiers, following him in their slow, camouflaged jeeps, had come to call for me. I had to go and attend to him by the roadside. Groaning in the grass, Idi was convinced the wrist was broken, and he curse…