Without Fail

headed for a white tent leading to a side door in the Senate Offices. There were two Secret Service Town Cars flanking the tent. Four agents out on the sidewalks, looking cautious and cold. Froelich drove straight for the tent and eased to a stop tight against the curb. Checked her position and rolled forward a foot to put Armstrong’s door right inside the canvas shelter. Reacher saw a group of three agents waiting inside the tunnel. One of them stepped forward and opened the Suburban’s door. Armstrong raised his eyebrows, like he was bemused by all the attention.
    “Good meeting you both,” he said. “And thanks, M.E.”
    Then he stepped out into the canvas gloom and shut the door and the agents surrounded him and walked him down the length of the tent toward the building. Reacher glimpsed uniformed Capitol security people waiting inside. Armstrong stepped through the door and it closed solidly behind him. Froelich pulled away from the curb and eased around the parked cars and headed north in the direction of Union Station.
    “OK,” she said, like she was very relieved. “So far so good.”
    “You took a chance there,” Reacher said.
    “Two in two hundred eighty-one million,” Neagley said.
    “What are you talking about?”
    “Could have been one of us who sent the letters.”
    Froelich smiled. “My guess is it wasn’t. What did you think of him?”
    “I liked him,” Reacher said. “I really did.”
    “Me too,” Neagley said. “I’ve liked him since Thursday. So now what?”
    “He’s in there all day for meetings. Lunch in the dining room. We’ll take him home around seven o’clock. His wife is home. So we’ll rent them a video or something. Keep them locked up tight all evening.”
    “We need intelligence,” Reacher said. “We don’t know what exact form this demonstration might take. Or where it will be. Could be anything from graffiti upward. We don’t want to let it pass us by without noticing. If it happens at all.”
    Froelich nodded. “We’ll check at midnight. Assuming we get to midnight.”
    “And I want Neagley to interview the cleaners again. We get what we need from them, we can put our minds at rest.”
    “I’d like to do that,” Froelich said.

    They dropped Neagley at the Federal lockup and then drove back to Froelich’s office. Written FBI forensic reports were in on the latest two messages. They were identical to the first two in every respect. But there was a supplementary report from a Bureau chemist. He had detected something unusual about the thumbprints.
    “Squalene,” Froelich said. “You ever heard of that?”
    Reacher shook his head.
    “It’s an acyclic hydrocarbon. A type of oil. There are traces of it present in the thumbprints. Slightly more on the third and fourth than the first and second.”
    “Prints always have oils. That’s how they get made.”
    “But usually it’s regular human finger oil. This stuff is different. C-thirty-H-fifty. It’s a fish oil. Shark-liver oil, basically.”
    She passed the paper across her desk. It was covered in complicated stuff about organic chemistry. Squalene was a natural oil used as an old-fashioned lubricant for delicate machinery, like clockwork watches. There was an addendum at the bottom which said that when hydrogenated, squalene with an e becomes squalane with an a .
    “What’s hydrogenated?” Reacher asked.
    “You add water?” Froelich said. “Like hydroelectric power?”
    He shrugged and she pulled a dictionary off the shelf and flicked through to H .
    “No,” she said. “It means you add extra hydrogen atoms to the molecule.”
    “Well, that makes everything clear as mud. I scored pretty low in chemistry.”
    “It means this guy could be a shark fisherman.”
    “Or he guts fish for a living,” Reacher said. “Or he works in a fish store. Or he’s an antique watchmaker with his hands dirty from lubricating something.”
    Froelich opened a drawer and flipped through a file and pulled a single sheet. Passed it across. It was a life-size fluoroscope photograph of a thumbprint.
    “This our guy?” Reacher asked.
    Froelich nodded. It was a very clear print. Maybe the clearest print Reacher had ever seen. All the ridges and whorls were exactly delineated. It was bold and astonishingly provocative. And it was big. Very big. The pad of the thumb measured nearly an inch and a half across. Reacher pressed his own thumb alongside it. His thumb was smaller, and he didn’t have the most