Daniel, a 26-year-old with Type 2 spinal muscular atrophy (SMA), a progressive genetic disorder that attacks core muscles and gradually limits the body's ability to move, breathe, and function, lives alone in a duplex on Agriculture Drive in Athens, Georgia. He works from home as a freelance social media manager for a small regional airline, responding to angry customer tweets. He cannot walk, has limited use of his left hand to operate his motorized wheelchair and keyboard, and lost intelligible speech after a jaw injury at age 21. He communicates through an iPad-mounted voice generator and a wordless, eye-contact-based system developed with those closest to him: his caregiver Marjani, a Pakistani immigrant who assists him mornings and evenings; his lifelong best friend Travis; and his mother, Angela, who raised him alone in central Illinois before he moved to Athens after college to live independently.
Daniel's mornings follow a rigid routine. He watches the local weather segment, and if the forecast is good, he wheels out to his front porch at exactly 7:21 a.m. For three weeks, he has noticed the same young woman walking past each weekday morning, a college student with a blue backpack who never looks at her phone. One morning, the woman makes eye contact with Daniel for the first and only time, gives him a small wave, and continues walking. Moments later, a drab tan Camaro pulls alongside her. Daniel catches two details about the driver: a shiny, chrome-tipped boot and a blue Atlanta Thrashers hat, merchandise from a defunct hockey team. The woman hesitates, glances back at Daniel, then gets into the car.
By Tuesday, the disappearance of Ai-Chin Liao, a 19-year-old Chinese visiting scholar studying veterinary medicine at the University of Georgia, dominates the local news. She has been missing for 72 hours. When Travis shows Daniel her photo over their regular Tuesday lunch, Daniel recognizes Ai-Chin as the woman who got into the Camaro. He texts Travis about what he saw, and that evening he creates his first-ever Reddit post describing the scene.
The next morning, Daniel finds the post downvoted into obscurity and deletes it. He and Travis call multiple precincts before leaving a message on the tip line, though Travis forgets to include Daniel's name. A young officer, Wynn Anderson, visits Daniel's home in response but is uncomfortable with Daniel's disability and leaves without gathering substantive information. That evening, Daniel receives a threatening email from an anonymous sender who references details from the deleted Reddit post, claims to have been driving down that street, and warns Daniel they are "about to become real close" (86).
Daniel cautiously responds, giving a false name and adopting a friendly tone. The sender identifies himself as Jonathan, claims Ai-Chin got in his car voluntarily, and says they are growing close. His messages oscillate between loneliness and hostility, expressing misogynistic grievances and self-pitying rants. Daniel finds himself drawn into the correspondence, recognizing a shared isolation. He also notices unexplained muddy boot prints on his front porch.
Throughout the week, the search for Ai-Chin intensifies. Daniel attends a vigil at the campus intramural fields, where he meets Jennifer, a student who lives near Ai-Chin. He sees Ai-Chin's parents; her mother gives Daniel a small wave identical to the one Ai-Chin gave him. At a larger rally the next day, Daniel meets Rebecca Lee, a Chinese American graduate student organizing the search. While talking to Rebecca, a piece of mucus lodges in Daniel's trachea, and Marjani has forgotten his cough assist machine, a device that clears airway obstructions. Daniel loses consciousness and survives only because part of the blockage dislodges when a bystander carrying him accidentally drops him. Rebecca drives him to the hospital.
When Officer Anderson returns to take a formal statement, Daniel reports the exact time, the tan Camaro, the Thrashers hat, and the chrome boot. But when Daniel mentions Jonathan's emails, Anderson dismisses them, identifying the emailer as Jonathan Carpenter, a known local figure who habitually calls police claiming responsibility for crimes he did not commit. Daniel feels relieved, believing his role has been reduced to that of a witness, though he continues emailing Jonathan out of sympathy, viewing Jonathan as a lonely person who needs someone to listen.
On Saturday, during a Georgia home football game, Daniel tailgates with Travis and Jennifer. He checks his email and finds increasingly agitated messages from Jonathan: declarations that he loves Ai-Chin and a claim that Ai-Chin remembers seeing Daniel on her morning walks. That night, Daniel discovers a final email caught by his spam filter, written entirely in Chinese. When he runs it through Google Translate, it reads as a plea from someone saying she is trapped, held by a man named John, and asking for help.
Daniel forwards the email to Officer Anderson, who agrees to visit Jonathan's home. Late Sunday night, Jonathan initiates a live Google Hangout text chat. He drops all ambiguity, confirming he drove down Agriculture Drive, offered Ai-Chin a ride, and took her to his home, where he has kept her captive. He reveals he has identified Daniel and taunts him: "you can't even get out of that chair" (238). A loud crack and flash of light follow, and Daniel falls.
Daniel wakes on the floor of his home. Jonathan, dressed in black and wearing the chrome-tipped boots, stands over him. He kicks Daniel, cracking his ribs, and begins cooking bacon in the kitchen. When Terry, the overnight orderly, arrives for his shift and confronts the intruder, Jonathan beats him unconscious with an aluminum baseball bat. Daniel jams his wheelchair forward, catching the cord on the refrigerator. The appliance yanks loose and blocks Jonathan's path, and Daniel escapes out the front door.
Daniel wheels through the dark streets toward St. Mary's hospital, but Jonathan catches up in the Camaro and forces Daniel to crash into a street sign, flipping his chair and knocking out two teeth. Jonathan crushes Daniel's left hand, the one that controls his wheelchair, and wheels him back to the house. Jonathan monologues while Daniel drifts in and out of consciousness, catching only fragments. Jonathan shows Daniel security footage on his phone of Ai-Chin, alive but captive in a storage shed, then eventually falls asleep in a chair. During the ordeal, Daniel manages to send a brief message to Travis through his chair's iPad.
A reply flashes on the screen: "We are here. I see you. We got you. Let's do this" (274). Daniel slams his wrist against the joystick, ramming his chair into the kitchen table. The crash splashes coffee onto Terry, who groans, revealing he is alive. The noise wakes Jonathan, who grabs the bat, but Marjani walks calmly through the front door as a distraction while police storm in from the back. Officers subdue Jonathan, shooting him in the leg. Travis and Marjani rush to Daniel's side.
In the aftermath, Daniel lies in a hospital bed, having nearly died multiple times. Ai-Chin was found locked in a storage shed behind Jonathan's duplex, terrified and hungry but physically unharmed. Terry survived with a broken jaw and concussion. Jonathan has been arraigned on felony kidnapping, aggravated assault, and attempted murder charges. Travis explains that when he received Daniel's message, he called 911, then Marjani, who called Officer Anderson; all converged on the house simultaneously.
Ai-Chin visits Daniel in his hospital room. She is composed and strong, not the helpless victim he had imagined. She hands him a letter written in Chinese, says "Thank you," and Daniel responds through his voice generator: "You. Are. Well. Come" (286). In the novel's closing passage, Daniel reflects that he is the lucky one: lucky to have people who love him, lucky to have lived fully despite his disease, and lucky to have changed the world through his actions. He affirms that he is not ready to die and intends to keep going.