Colin Lee and his six-year-old daughter, Maisie, are enjoying a day at the western coast of Pelican Island, their home, when Maisie discovers a washed-up corpse infected with the gray pox, a deadly plague destroying the mainland's population. Despite only a few seconds of contact, Maisie contracts the pox and is placed in quarantine. Luckily, Maisie's aunt, Audra, is one of the small island community's handful of plague doctors. After Maisie's horrific discovery, Audra closes the beaches and scours them for the dozens of corpses that have begun to wash up daily. Pelican Island has thus far escaped the plague, but Audra knows it's only a matter of time - and Maisie's only getting sicker. She connects with other small community scientists around the world, and they form a group known as the Network, determined to share research and find a cure at any cost. A member of the Network and one of Audra's closest friends releases stolen data from major research organizations and goes missing within a few hours. The remaining Network is horrified to discover the cure has already been researched, but has quietly been provided to only the rich, old, and white. Their missing member is nowhere to be found, but the data she supplied will help them produce results. Working with the new data, Network labs quickly develop an experimental cure of their own. Although it has a high mortality rate and needs more human trials, Colin steals a vial to give to Maisie. She survives the treatment and tests negative for the disease, but Audra loses her medical license from her perceived carelessness in enabling Colin to steal the vials. Those who have received the cure are encouraged to travel and spread its effects to others through respiratory droplets. Colin and Maisie leave for the mainland, and Audra must go home to her empty house and decimated career. Just as her isolation begins to sink in, the Network's biggest sponsor arrives. He promises her their missing member is still alive, but will be hunted by the research organizations she stole data from for many years. He offers Audra a new position, one that doesn't require a medical license. Gratefully, she accepts.