It was, quite literally, my area of professional expertise, and Julian had left me alone in a hotel room with nothing but the one thing he did not know how to take: my training.

And as I sat there, the professional part of my mind waking up and taking over from the frightened wife, an old, seemingly useless piece of data floated up from somewhere deep in my memory.

A seven-digit sequence.

Years earlier, my former director, a humorless, fastidious man named Martin Shaw, had instituted a mandatory safety drill for every senior consultant in the firm.

He had forced each of us to memorize, by rote, one single international emergency contact number, and to be able to recall it under stress, without a phone, without a device, from memory alone.