The 1983 novel's plot revolves around the outbreak of an extremely virulent form of rabies, introduced to the London Heathrow Airport by a puppy smuggled from Israel on an Alitalia jet headed for New York City.
Due to the mutated nature of the virus, its incubation period has been reduced to hours instead of weeks or months, and its method of transmission now follows more closely that of the flu.
Whilst tight security is being deployed by the head of the Aviation Security, Major Lawford, along with his colleagues: Colonels Donovan of the MI6 and Rasimov of the KGB, the Heathrow Medical Centre, headed by Dr. Luke Komarovsky, becomes informed that a nun from a convent near Lagos Nigeria, who was travelling on the Alitalia Boeing 747 en route to New York City via Heathrow, has become ill.
Dr. Komarowsky, who in the past has been a scientist, was working, along with three other doctors, each of whom will make an appearance later in the book: Dr. John Hamilton, Dr. Matthew Laverick, and Dr. Coro Deveroux, in a team headed by the world-renowned microbiologist Dr. Frederick Lieberman.
Their work in a laboratory at Wolfenden House is veiled in mystery, but their goal (four of them were called either the nucleus or evangelists of Messiah Lieberman) was the 'holy grail' of microbiology - creation, through genetic reorganisation, of general immunity to bacterial, viral and oncological diseases.
This event leads to Luke Komarowsky abandoning the field of virology and science altogether, and puts him in his present position of the head of the Heathrow Airport medical unit.
Airport Security, not being informed of the reason for the presence, and focusing on the arrival of the Soviet diplomatic contingent, clears out the lounge and moves the passengers into the general transit.
Then the doctors of the medical service, dispatched to the Transit of the Terminal 2 after a brawl has erupted there, reports that he found some of the brawlers showing signs of epileptiform seizures.
As the outbreak spirals out of control, the remaining doctors - Komarowsky, Deveroux, Hamilton and Lieberman, and a select list of other people, including the writer on whose notes the novel is supposedly based are locked in the tower which has been turned into a fortress.
Dr. Lieberman, who, hiding behind a supposed Jewish background, is in reality a former SS doctor Siegfried Stadler, who headed the plan of improving the mankind on genetic level, and worked directly for Himmler in Auschwitz.
As the rabies spreads rapidly amongst the remaining AS officers, Luke, who has decided the best way to certainly bring back a sample is to infect himself, runs into Dr. Matthew Lawerick (the fourth of Lieberman's 'evangelists' from Wolfenden) who has been brought to insanity following his desperate attempts to save his wife from the disease.
Hamilton has notified the commander of the blockade that he will be in regular telephone contact, and if he does not call, that means the vaccine/serum failed, and Heathrow is to be 'sanitized' - completely cremated by the army.
He proposes to US to conduct a nuclear cremation of Heathrow (and maybe entire London, since there has been, later shown, mistaken, alarm that a case appeared in the city), and apparently threatens that if US refuses to cooperate, Soviet Union will proceed with the operation on its own.
All of a sudden, the first shocking discovery is made - Hamiltons clock has stopped, he failed to make the final call that would announce, without a doubt, the success of the serum, and save Heathrow, because of it.
The book ends with the epilogue written by the supposed author, who while visiting Gabriel at the mental hospital found out about destiny of Heathrow prisoners and his friend, Daniel Leverquin, who was at the airport and chronicled the epidemic.
He describes the Heathrow outbreak as contained, and documents that debate is being held as to what to do with the ruins of the once great airplane hub and Gabriel latest escape from mental hospital.