Sir, I need you to reallocate to seat 32B, the flight attendant said. We have a family that needs to sit together, and your seat is the only one available.

The old man found his aisle seat, the one he’d paid extra for, months ago because of a service injury. I booked this for medical reasons, he said quietly, but she didn’t budge.

If you don’t reallocate, we can’t close the doors. Nine minutes later, the cockpit door opened, and the captain entered. What he did next altered the meaning of that flight forever.