Which meant she had made a giant circle back to the same question as yesterday: What was he planning?

Sara considered the characteristics she had gleaned about Dash. Primary among them was that Dash was a highly organized leader. The Camp had not appeared overnight. There was the feeling of a planned community about the place. The two separated areas. The greenhouse. The Structure. The readily available food. The way the women and men were dressed. The compliant obedience of the followers. The sense that rules were being followed.

Rules made by Dash.

He was clearly capable of strategizing and long-term planning, which was harder for most criminals to pull off than the average non-criminal would believe. Dash had also passed one of the biggest deterrents to male criminal behavior: turning thirty. Sara guessed he was in his mid-forties. He did not come across as well-educated, but he exhibited a type of intelligence that served a very specific purpose. You couldn’t persuade a group of people to give up modern life if you didn’t have a certain amount of emotional intelligence. All of which pointed to a very high level of arrogance. People didn’t believe in you unless you convinced them that you believed in yourself.

Sara tried to slot Gwen into the equation. She was loath to assign Lady Macbeth qualities to another woman, but there was something sinister about Gwen from the very beginning. Her complicity in the measles outbreak. The way she used Bible verses to scare her children. The callous disregard for life. Sara wasn’t even sure that Gwen was qualified to be a nurse. She was clearly willing to do Dash’s dirty work. All she had needed was a nod from her husband and as soon as his back was turned, Gwen was suffocating Tommy to death.

Sara could easily see someone like Gwen coaxing and cajoling Dash, pushing him toward even greater acts of terrorism. Whatever Dash was planning, Sara had no doubt that Gwen had approved every detail. Maybe even added some sadistic details of her own.

But, what?

Sara started pacing the cabin again, this time to work her brain instead of her glutes.

Post-9/11, explosions and bombs had not become ordinary in American life, but neither were they wholly unexpected. The shock value had diminished with each attack. Mass killings, shooting sprees, school shootings—all of these attacks still horrified Americans, but by the following week or month, they would resume their regular lives until news came of the next attack.

Sara could imagine that Dash was aware of the diminishing returns of these sudden acts of violence. Every time she tried to put herself inside his head, she came out thinking that what Dash really wanted to do more than anything else was to make a name for himself.

Which brought her back to Michelle.

Which brought her back to a biological attack.

If you wanted an agent that scared the shit out of people, anthrax, with its 90 percent mortality rate, was highly effective. The 2001 Amerithrax attack had paralyzed the postal service and parts of government. The spores could be aerosolized, but person-to-person transmittal was not going to happen. Also, because of the earlier attacks, finding a source bacterial strain was nearly impossible.

Botox was another option, but you’d need to raid every single plastic surgeon’s office in America, and then you’d still end up only having enough to kill a handful of people. And you would have to inject them individually, so—

Sara paced in a circle.

She mentally flipped through her basic how nature can murder you knowledge from medical school. Rickettsiaceae, Bunyaviridae, Marburg, Chlamydophila psittaci—all incredibly dangerous and all almost impossible to weaponize. Vaccines, antibiotics and quarantine procedures deprived most of these viruses and bacteria from infecting multitudes.

Dash would want multitudes.

There were so-called select agents such as ricin, staphylococcal enterotoxin B, botulinim toxin, saxitoxin and myriad mycotoxins. But the possession, transfer and use of these organisms was heavily regulated by the Select Agent Program. Not that a regulatory body was necessary. Most of the toxins could be whipped up in the average kitchen. You didn’t need a secret greenhouse to cover your tracks. And you didn’t really need a sophisticated toxin to make a huge impact.

In 1984, a rogue faction of the Rajneeshee had easily synthesized enough Salmonella enterica Typhimurium to sicken over 750 people in the state of Oregon. In Chicago, in 1982, a still-unidentified poisoner had laced Tylenol capsules with potassium cyanide and forever altered the way medications were packaged.

Sara considered the Structure where Tommy had died. At least two stories tall. An open main floor, a balcony ringing the second floor. Stairs up the middle.

Could anthrax be inserted into an air conditioning unit?

If that was possible, someone would’ve tried it by now.

Legionellosis occurred naturally in fresh water.

Exposure was hit-or-miss, not person-to-person and the bacterium only had a 10 percent mortality rate.

“Crap,” Sara repeated.

Right back at the beginning again.

She had to stop pacing before her muscles cramped. She couldn’t do another lunge. She was out of lyrics except the one she couldn’t recall about the waitress working at the bar. Only Will could tell her the name of the song. She would hum it, and he would tell her that she couldn’t hum, and in the end, he would guess the song anyway.

Sara pressed her fingers into her eyes.

She could not let herself fall into another crying jag. She had passed the stage of longing for Will and had returned to worrying about him. Had he seen the heart she had left for him at the motel? Did he know about the code inside the medication list?

Tessa should be in Atlanta by now. Sara wanted her sister to hold Will. No one ever really held him. Sara wanted Tessa to tell him that everything was going to be okay. She wanted—needed—her mother to wrap Will into the family to protect him because with every passing hour, Sara found herself closer to accepting the fact that she was not going to make it home to any of them.

“Sir.” Lance was outside the cabin door. Sara heard him shuffle to his feet. She hadn’t known him to take a break in the last two days.

As usual, whatever Dash told him was too low for Sara to hear. His soft murmurs made her miss Will’s deep, masculine tone even more.

Lance said, “Understood, sir.”

Sara’s ears strained as she listened for the key sliding into the padlock. She was as anxious to go for a walk outside as her dogs were when Sara got home from work.

Finally, the padlock clicked. The door opened. Dash stood on the log that served as a step. His sling was crooked. His hand was too low. “Dr. Earnshaw, I’m about to take lunch with my family. My little girls have specifically requested your presence.”

Sara wanted to kiss each and every one of his daughters.

She pulled up her toga and stepped down into the sunlight. The sweat on her skin turned to steam in the heat. She had given up longing for fresh clothes. Right now, she’d settle on any part of her body being immersed in clean water.

Dash adjusted the sling. The strap had worn a spot on his neck. He said, “I’ve heard our children are not responding to your ministrations.”

“They’re not responding to the medications,” Sara told him. “Are you sure they’re legitimate? The black market isn’t always—”

“I appreciate your concern, Dr. Earnshaw. Our source wouldn’t sell us bogus goods.”

Our source.

Sara wondered if the source was Beau. If Beau was in custody. If Will knew that Sara was doing her damnedest to reach out to him.

“Whoa there,” Dash said.

Lance had stumbled. Sara did a double-take as he righted himself. Her sentry looked like he should be on his back. Pale complexion, heavy eyelids, shortened breaths. She had heard him running down to his makeshift toilet most of the night.

Sara continued her walk toward the clearing. Lance should really see a doctor. Dysentery killed around one hundred thousand people a year.

Dash said, “Gwen tells me that Adriel had a fitful night.”

“I’m worried that the children are developing a secondary issue. Some kind of virus or bacterial infection.” She ducked as Dash reached past her, but he was only pushing away a branch. “I’d like to check on them again.”

“I’ll make sure you have as much time in the bunkhouse as you need.”

“Thank you.” Sara heard her voice crack with gratitude. She cared about the children, but the thought of being freed from her cabin cell was elating. “Benjamin, especially, is not doing well.”

“Gwen would say suffer the children.”

Sara had seen proof that Gwen didn’t care who suffered, so long as it served Dash’s purpose.

He said, “If God does exist, and He knows about the suffering of our precious lambs, then He is no God that I would seek to know.”