Soon enough, these sites were flooded with requests that went far beyond cancer. Diagnostic agents, vaccines, antimicrobials, even designer psychoactive drugs—all appeared on the menu. What people did with these bio-designs was anybody’s guess. No international body had yet been created to watch over them.

So, in November of 2016, when a first-time visitor with the handle Cap’n Capsid posted a challenge on the viral-design site 99Virions, no alarms sounded; his was just one of the 100 or so design requests submitted that day. Cap’n Capsid might have been some consultant to the pharmaceutical industry, and his challenge just another attempt to understand the radically shifting R&D landscape—really, he could have been anyone—but the problem was interesting nonetheless. Plus, Capsid was offering $500 for the winning design, not a bad sum for a few hours’ work.

Later, 99Virions’ log files would show that Cap’n Capsid’s IP address originated in Panama, although this was likely a fake. The design specification itself raised no red flags. Written in SBOL, an open-source language popular with the synthetic-biology crowd, it seemed like a standard vaccine request. So people just got to work, as did the automated computer programs that had been written to “auto-evolve” new designs. These algorithms were getting quite good, now winning nearly a third of the challenges.

Within 12 hours, 243 designs were submitted, most by these computerized expert systems. But this time the winner, GeneGenie27, was actually human—a 20-year-old Columbia University undergrad with a knack for virology. His design was quickly forwarded to a thriving Shanghai-based online bio-marketplace. Less than a minute later, an Icelandic synthesis start‑up won the contract to turn the 5,984-base-pair blueprint into actual genetic material. Three days after that, a package of 10‑milligram, fast-dissolving microtablets was dropped in a FedEx envelope and handed to a courier.

Two days later, Samantha, a sophomore majoring in government at Harvard University, received the package. Thinking it contained a new synthetic psychedelic she had ordered online, she slipped a tablet into her left nostril that evening, then walked over to her closet. By the time Samantha finished dressing, the tab had started to dissolve, and a few strands of foreign genetic material had entered the cells of her nasal mucosa.

Some party drug—all she got, it seemed, was the flu. Later that night, Samantha had a slight fever and was shedding billions of virus particles. These particles would spread around campus in an exponentially growing chain reaction that was—other than the mild fever and some sneezing—absolutely harmless. This would change when the virus crossed paths with cells containing a very specific DNA sequence, a sequence that would act as a molecular key to unlock secondary functions that were not so benign. This secondary sequence would trigger a fast-acting neuro-destructive disease that produced memory loss and, eventually, death. The only person in the world with this DNA sequence was the president of the United States, who was scheduled to speak at Harvard’s Kennedy School of Government later that week. Sure, thousands of people on campus would be sniffling, but the Secret Service probably wouldn’t think anything was amiss.