The narrative opens in a Frankfurt disco, where an American traveler feels euphoric and socializes intensely, unaware that he was infected days earlier with a biological weapon and is still in the infection’s incubation period. He is infected with a genetically modified strain of Yersinia pestis, the bacterium that causes plague. According to former U.S. Army bacteriologist Dr. Henry Heine, the weapon was engineered to induce a neurochemical high, encouraging the host to spread the disease before symptoms become debilitating. Heine explains that the Soviets inserted an endorphin gene to create this effect, making infected individuals want to go out and socialize even while sick.

After dancing until dawn, the traveler returns to his hotel, where the euphoria wears off in the shower, replaced by anxiety, confusion, and fright. At airport security, he notices petechiae, small red spots caused by bleeding beneath the skin, on his forearms. Despite worsening symptoms, he boards a flight to Dallas-Fort Worth with 420 other passengers. During the flight, his condition deteriorates rapidly into severe pain, coughing, and vomiting, and after he collapses in the lavatory, his sputum sprays the walls and bloody vomit contaminates the sink and floor. Parts of his lungs begin to die as sepsis sets in. The author traces the development of recombinant plague to the Soviet “Bonfire” bioengineering program, conceived by Igor Domaradskij, which sought to transfer DNA from one germ into another and eventually produced a hypervirulent, antibiotic-resistant plague weapon. Jacobsen then describes its further development into a “two-strike” chimera bioweapon capable of combining two disease agents in one weapon and notes that Kanatzhan Alibekov later said he authorized the Chimera project. As the plane nears Dallas, the critically ill traveler coughs directly into a flight attendant’s face while the plague bacteria linger in the cabin air.

In 1971, Stanford University biochemist Paul Berg conducted the world’s first gene-splicing experiment, creating a “recombinant DNA” molecule by combining the DNA of two different viruses. This creation of a biological “chimera” marked the dawn of genetic engineering. The following summer, Berg’s graduate student Janet Metz attended a Cold Spring Harbor workshop and told her teacher, virologist Robert Pollack, about the experiment. Pollack warned Berg about the potential danger of introducing DNA from SV40, a monkey virus known to cause cancerous tumors in laboratory animals, into E. coli bacteria, fearing that bacteria carrying the viral DNA might escape and cause cancer. Berg initially dismissed the risk but reconsidered after consulting Nobel Prize-winning microbiologist Joshua Lederberg and concluded that he could not guarantee the experiment posed no risk.

Prompted by these concerns, Berg and ten other scientists published a letter in the Proceedings of the National Academy of Sciences calling for a temporary moratorium on the research. Following public debate over the risks, Berg formed a committee that resulted in the 1975 Asilomar Conference, where some 150 microbiologists, physicians, lawyers, and a few journalists agreed to continue recombinant DNA research but under stringent new safety guidelines for biocontainment. However, as Berg and fellow Nobel laureate David Baltimore later recalled, the conference focused on the science without discussing the potential application of the technology to biological warfare. The chapter concludes by connecting this omission to the Soviet Union’s covert biological weapons program. Jacobsen states that the Soviet Union began pursuing biological weapons using recombinant DNA techniques soon after signing the Biological Weapons Convention, while former program deputy chief Ken Alibek later claimed that the Soviet program developed and stockpiled hundreds of tons of anthrax and dozens of tons of plague and smallpox for use against the United States and its allies.

In November 1989, senior Soviet scientists and military officials gathered at a secret facility in Obolensk, Russia, to review their biological weapons program. Known as Biopreparat, the top-secret research and development branch was concealed behind a civilian organization ostensibly producing vaccines and other medical countermeasures. According to research scientist Sergei Popov, the program sought to kill large numbers of people and inflict a psychological blow on the United States by developing weapons that could render American vaccines and antibiotics ineffective. Popov said this could cause “catastrophic distrust” of the government and military.

At the meeting, Popov presented a proof-of-concept experiment. His boss, molecular biologist Lev Sandakhchiev, had previously singled him out for scientific espionage and sent him on a six-month sabbatical to the Laboratory of Molecular Biology at the University of Cambridge, where he studied DNA synthesis under microbiologist Michael Gait. Rabbits were exposed to an aerosolized, genetically engineered pathogen. At first, the animals displayed the expected tuberculosis-like symptoms. However, several rabbits then developed a second set of symptoms: paralysis. Ken Alibek, the deputy chief of Biopreparat, and the other officials in attendance immediately recognized the significance of the experiment. According to Alibek, a single genetically engineered agent had produced symptoms of two different diseases, demonstrating the sought-after concept of a two-stage, or chimera, bioweapon. Alibek declared the test a success and later wrote that “a new class of weapons had been found” (8).

Around the same time as the Obolensk meeting in 1989, a high-ranking Soviet scientist, Vladimir Pasechnik, defected to the United Kingdom. Attempting first to defect at the Canadian embassy in Paris, he had not been believed and had been turned away; desperate, he had then called the British embassy from a pay phone, and British intelligence had taken him seriously. During his debriefing with British intelligence officer Dr. Christopher Davis, Pasechnik revealed the scale of the illegal Soviet bioweapons program, Biopreparat. He disclosed that his teams had developed biological weapons and methods for deploying them, including modifying cruise missiles to fly beneath U.S. radar and disperse aerosolized clouds of plague and other pathogens over large populations. Pasechnik had also developed a method for stabilizing plague microbes for widespread dissemination.

Davis interpreted the weaponization of plague as a strategic weapon for mass extermination, describing it as a “nuclear equivalent” that could kill a population while leaving infrastructure intact. The text then provides a “History Lesson” on plague, recounting Gabriele de’ Mussi’s disputed account that the Black Death began after Mongol forces catapulted plague-infected corpses into the Genoese-held fortress of Caffa in 1346. Jacobsen acknowledges that whether this event caused the Black Death remains impossible to determine. The chapter then explains plague’s three forms: bubonic (spread by fleas), septicemic (infecting the blood), and pneumonic (infecting the lungs). Pneumonic plague is transmissible from person to person, and the text states that it is fatal if left untreated and that antibiotics must enter the bloodstream within 24 hours of infection. The chapter returns to 1989 by connecting plague’s historical devastation to Davis’s alarm over its weaponization. Pasechnik’s disclosures revealed to Western intelligence the scale and scientific sophistication of the Soviet biological weapons program.

Following Vladimir Pasechnik’s defection, a second Soviet scientist also defected, although his identity remains secret. British intelligence shared Pasechnik’s disclosures with the CIA, which sent Nobel laureate Joshua Lederberg to interview him and assess his account. Lederberg later told Congress that he gave Pasechnik’s story “high credibility.” After the subsequent collapse of the Soviet Union in 1991, concern increasingly turned to the possibility that terrorists might acquire biological weapons. This fear was amplified by the 9/11 terrorist attacks and the 2001 anthrax letter has never formally been solved. In response, the U.S. government expanded biodefense funding, and in 2004 Congress launched Project BioShield to fund the development of medical countermeasures.

Jacobsen describes the resulting system as a “biodefense industrial complex” (34), accompanied by an expansion of high- and maximum-containment laboratories. BSL-3 laboratories handle dangerous pathogens such as anthrax and plague, while BSL-4 laboratories are designed for the most dangerous pathogens for which no treatments or vaccines are known. By 2007, a congressional audit identified at least 1,356 BSL-3 and 15 BSL-4 laboratories in the United States. It also found that “no single federal agency” (34) was responsible for assessing the aggregate risks associated with the expansion of these laboratories. Similar facilities were also being developed in countries around the world for biodefense-related research.

The chapter connects this expansion to the growth of gain-of-function research, in which scientists deliberately alter pathogens to give them new capabilities, such as greater transmissibility, easier human infection, or the ability to evade immunity. Proponents argue that such experiments can help scientists understand biological threats and develop countermeasures, while critics argue that they create global catastrophic risks and can be indistinguishable from illegal biological weapons work. The chapter closes by raising the possibility that a genetically modified pathogen could escape from a laboratory or be deliberately released. Former presidential adviser Andy Weber describes gain-of-function research as “biological weapons engineering” (35).

The rapid, post-9/11 expansion of biosecurity labs normalized a highly controversial field of research known as “gain-of-function.” This type of experiment involved deliberately altering pathogens to make them more dangerous—for example, more transmissible or more lethal—in order to study them. Proponents argued such research could help scientists understand biological threats and develop vaccines and other medical countermeasures. Jacobsen cites Dr. Anthony Fauci’s 2012 argument that the benefits of gain-of-function experiments and the resulting knowledge outweighed their risks. Critics warned that such research could create global catastrophic risks.

High-profile experiments, such as the Australian mousepox experiment of 2001—which inadvertently made a relatively mild virus lethal to previously vaccinated mice—and the 2011-2012 H5N1 ferret flu experiments conducted in the Netherlands and the United States, which made H5N1 capable of spreading through the air in the experimental model, intensified the debate. In 2014, the Obama administration enacted a temporary pause on some gain-of-function studies, but the policy was later reframed as risk management under the term “Potential Pandemic Pathogen Care and Oversight” (38), or P3CO. The COVID-19 pandemic brought the issue to global attention as questions arose over whether SARS-CoV-2 had emerged naturally or had been genetically engineered in Wuhan laboratories. The chapter concludes by noting that a 2025 global survey—conducted by Global Biolabs, a collaboration between the Bulletin of the Atomic Scientists, King’s College London, and George Mason University—identified 110 BSL-4 labs in thirty-four countries and 3,515 BSL-3 labs across 149 countries, possibly more. Jacobsen identifies this global network of high-containment laboratories as the setting from which the book’s biological-war scenario begins.