Chloe held up a small silver phone she had pulled from the seat cushion. “Ma’am,” she asked loudly, “why does this phone have your name on the lock screen, and why is it ringing from the airline’s security line?” The woman went rigid. Passengers leaned into the aisle. A flight attendant stepped forward, reaching for the phone, while the woman’s bare foot slid slowly back under her seat.

The phone buzzed again, and Chloe turned the screen toward the cabin. A photo of a different woman filled it, smiling, with a message beneath: Where are you? The real passenger for 14A has been waiting at the gate for an hour. My stomach dropped. The woman in Chloe’s seat grabbed her handbag and stood up fast. Behind her, a man in a navy jacket rose from row 13 and quietly flashed a badge.