Craig Dixon, a 'turbulence expert' staying at Boston's Four Seasons, is summoned by a lisping 'facilitator' to take Allied Airlines Flight 19 from Boston to Sarasota. Dixon, exhausted from a recent Seattle run, protests but knows refusing carries dire consequences. He boards in his usual middle seat aft of the starboard wing, seated between a chatty widow named Mary Worth, who is meeting online friends in Florida, and a surly businessman, Frank Freeman.

Over South Carolina, the plane hits violent clear air turbulence. Passengers are thrown about; Mary grabs Dixon's hand, terrified. Dixon shuts his eyes and lets the terror take him completely, vividly imagining the plane crashing and burning. This intense, prepared terror is what he is paid for: it somehow keeps the aircraft aloft. The plane stabilizes. Captain Stuart reassures the passengers, and the flight lands safely.

At the Sarasota airport, Dixon learns Mary's ride has fallen through and offers her a lift in his limo to Siesta Key. During the drive, he reveals his secret occupation: an organization, possibly using precognates, identifies flights that will encounter dangerous turbulence and places terrified, talented passengers aboard whose mental terror saves the plane. He explains he is recruiting her, motivated partly by altruism and partly by a bonus that brings him closer to retirement. He withholds that one cannot quit.

Mary listens, fascinated but skeptical, and gives Dixon her phone number before reuniting with her widow friends. Weeks later, after Mary has nearly forgotten Dixon, the lisping facilitator calls her. The next day, Mary boards Jetaway Flight 694 to Dallas, in coach just aft of the starboard wing, middle seat, refusing food and drink. Turbulence strikes over Oklahoma.