Reacher was supposed to supply his own pocket junk, so next up was ID. It had his real name and his photograph on it, but a master sergeant’s rank, and an infantry unit sufficiently generic to be plausible for a guy deployed with Special Forces, shooting individuals one at a time from a mile away.

‘How do I communicate with the colonel?’ Reacher asked.

‘Try the telephone,’ the supply guy said.

‘Sometimes hard to find a phone in a hurry.’

‘There’s no danger,’ the supply guy said. ‘It’s all just talking.’

The woman with the fanny pack and the headband crossed the Potomac on the Francis Scott Key Bridge, high above the water, running hard, die straight, through the hot swampy air, a glorious unbroken sprint, heading for Georgetown but not planning to get there. She was going to turn right on M Street, which became Pennsylvania Avenue, all the way to Washington Circle, and then New Hampshire Avenue to Dupont Circle, and then Mass Ave the rest of the way to the Capitol itself.

A crazy route, geographically, but any other option was either less or more than five miles, and five miles was what she ran. To the inch. Anyone else would have used her car’s odometer, on a quiet Sunday morning, but she had bought a surveyor’s wheel, a big yellow thing on a stick, and she had walked with it four separate times before she came up with eight thousand eight hundred yards exactly, and not a single step less or more. Precision was important.

She ran on. By that point she could feel a wide sweat stripe all the way down her back, and her throat was starting to burn. Pollution, hanging over the sluggish river, a visible cloud. But she dug in and pushed on, long, long strides, fast cadence, arms pumping. Her headband was soaked. But she was ahead of schedule. Just. Many variables ahead, but she had a chance of making it. Five miles in thirty minutes. Eight thousand eight hundred yards in one thousand eight hundred seconds. Fourteen and two-thirds feet a second. Not an international distance, so there was no world record. No national record, no Olympic record. But the greats might have done it in twenty-four minutes. So thirty was acceptable. For her, with traffic, and lights, and office workers in the way.