The last known time it was used militarily was the US Civil War in the 1860s. It wasn’t a subtle or clever pathogen—when ingested it simply triggered a bacteriological war inside a digestive tract, attacking the vital organs and quickly leading to internal haemorrhaging, massive blood loss and a painful death. It didn’t kill everyone it touched—it didn’t have to. Even if it could render thousands of people incapacitated from one poisoned water supply, it destroyed morale, diverted resources to sick people and generated societal panic, whether an army camp or a city.

Yousef’s achievement was to isolate the strain that could be stabilised—as far as such an aggressive pathogen could be stabilised—and manipulate it so that when it met water it would thrive rather than degrade.

He walked the length of the underground lab, pondering his quest. His journey through high school in Pakistan and then university had led him to America, to Stanford, where he finished his PhD in bacterial engineering. His PhD was funded by the US Army, and he was offered a position in one of their labs. Little did they know that the gifted Pakistani was the son of a farming family from southern Iran. Yousef’s mother had been orphaned in the mid-1950s, when a French oil company had disposed of its drilling chemicals in a dry channel. That wadi was also a recharge for an ancient aquifer used by farming communities. His mother had watched her parents die in a crappy hospital, from internal injuries, because of French greed. His mother’s sister—the Doctor’s beloved Aunt Lavi—was brain-damaged from the poisoning and lived out her days in her sister’s house, singing childish ditties for her nephew and niece. His mother’s once-proud landowning family had been torn apart by the Westerners, their lives diminished, reduced to living in their adopted country of Pakistan. His immediate family wasn’t sold on vengeance. His sister was influenced by their kindly and entitled father—a man who had walked away from his Pakistani culture and thought nothing of adopting Western mannerisms. Yousef, meanwhile, had increasingly aligned himself with his Iranian mother and her rage towards the French. He had a good mind and a spectacular education, and he had vowed to humble the arrogant Franks with his greatest weapon—his superior intellect.

The day came when, as an associate professor at the National University in Islamabad, he’d returned to his office after teaching a class on bacterial toxins to find a suave but dangerous-looking man waiting. The man, whom Yousef would only ever know as ‘the Colonel’, offered him a job with his own lab and staff.