I woke up in our Thailand hotel and my husband’s family was gone. My phone, passport, and flight home were gone too. Then I found his note.

Suddenly, an old, seemingly useless piece of data floated into the forefront of my mind. A seven-digit sequence.

Years ago, my former director, Martin Shaw, had instituted a mandatory safety drill. He forced every senior consultant to memorize one international emergency contact number. I had mocked him relentlessly for it. No one memorizes numbers in the digital age, Martin, I had teased. Exactly, he had replied, utterly humorless.