Something far worse happened in Brazil in 1987, when scavengers looting a defunct hospital came across abandoned teletherapy equipment. Fascinated by the deep blue light the cesium chloride emitted, they stole it, then sold it to a junkyard owner who planned to fashion it into a ring for his wife. His young niece painted herself with the blue powder dust scraped off the source. Other relatives used it to mark crosses on their foreheads. In what became known as the Goiânia accident, 249 people total were contaminated. Twenty people were hospitalized, four of whom died (including the junkyard owner’s wife, niece and two workers who initially hammered open the lead casing).

In the aftermath of that incident medical facilities learned their lesson, keeping a tighter lid on used equipment. However one industry remained notoriously lax: oil production. X-ray radiography cameras were used to inspect oil and natural gas pipelines, making sure they’d withstand extreme stress. More technologically advanced cameras were constantly becoming available, and the older ones were discarded. Buried deep in the core of those cameras were gamma radiation sources, most commonly iridium-192 and cobalt-60. You could block other forms of radiation by simply holding up a cloth. But thanks to their short wavelength, gamma rays could penetrate skin. Exposure for even a brief period almost guaranteed a painful death.

Which was why Randall was being so careful. In addition to a heavy-duty protective suit and apron, he was using a respirator and wearing heavy gloves and boots. Thor was clad in a similar outfit; Randall was surprised they’d managed to find one in his size. Randall was using a blowtorch to remove the source material from the camera’s lead container. The cameras he had diverted were Philips 160 kV constant-potential X-ray systems, designed to inspect large oil and gas pipes. Hence the need for the flatbed trucks-the housings were enormous, which guaranteed that camera operators worked at a safe distance from the X-rays.

The box holding the iridium wasn’t large, but thanks to the lead casing it was extraordinarily heavy. Once he got the case open, there would be temporary exposure to the source material until he transferred it to the other container. He kept checking the dosimeter clipped to the outside of his suit. It was still within normal ranges, although far beyond what a human should sustain on a daily basis. The dots marching up the badge ranged from 5 rads, the lowest level of radiation exposure, to 100 rads, or “your skin is about to bubble and fall off.” Right now the dot marking 5 rads was completely black. It was a good thing he wasn’t planning on having any more kids.

The thought reminded him of Madison. Randall wondered if she was still alive. His bumbling attempt to secure proof of life had failed miserably. He cringed at the memory of posturing in the cracked bathroom mirror, thinking he’d shown them. The minute they brought him back into the main room, any illusion that he had control over the situation vanished.

“So? Where’s my proof of life?” he had asked, trying to remember everything Jake told him. Be tough, they clearly need you more than you need them, Jake advised. Seize control of the negotiation process, don’t let them dictate all the terms. And by the way, your daughter is probably already dead, was the addendum, but he knew Jake hadn’t dared say it aloud.

“Someone wants to talk to you,” the bald man in charge said, handing him a phone.

“Dr. Grant?” The voice was deep, with a distinctive twang.

“I want proof that my daughter is still alive.”

There was a pause before the man spoke again, sounding bemused. “Oh, you would, would you?”

“If you want my help, I want proof.” Randall tried to sound forceful, self-assured, but his resolve was wilting.

“Let me make something clear to you, Dr. Grant. At the moment, you and every member of your family live and die at my discretion. And that includes Bree and Audrey.”

“Bullshit. They’re somewhere safe, you can’t get to them.”

“Oh, you mean your mother-in-law’s place in Massachusetts? She has a hell of a rose garden.”

Randall’s blood ran cold. He’d been a fool to listen to Jake and Syd, he should have hidden them better. Of course it would be child’s play for someone with access to the inner workings of the facility to uncover their whereabouts.

“I’m sending you a text,” the voice said.

Randall pulled the phone away from his ear and squinted at the image. It was pixelated by the cheap camera, but he could still discern the outlines of his mother-in-law’s house. And Audrey’s VW was parked in the driveway.

A tear snaked down his cheek as he pressed the phone back to his ear.

“I have men stationed nearby who can be at the house in under five minutes. And they won’t kill them quickly. Those men with you now? They’re civilized compared to the ones I sent.” The sound of a throat clearing, then the man asked, “So I’m assuming we’ll have your full cooperation?”

“I’ll need tools,” Randall responded dully.

“Rest assured, Dr. Grant, you’ll have everything you need. Now put Dante back on.”

Dante. The bald leader had a name now. Of course, if they weren’t bothering to conceal their identities, obviously the minute he finished the job he was a dead man.

He glanced at Thor, who absentmindedly scratched himself. Randall was to transform the materials into a radioactive dust that would spread a cloud of death when the bombs detonated. Someone else was constructing the bombs, he had no expertise in that field. But he knew radioactive matter. For the past two decades it was all he’d studied. He could recite the properties of each isotope, knew the half-life of every source. And chances were Thor didn’t know an isotope from an isobar. Randall might not be able to stop this group without putting his family in horrible danger, but he could diminish the fallout from what they had planned. Literally.

Randall bent to his task again. Despite the media hysteria in 2002 when Jose Padilla was accused of trying to build a dirty bomb, fashioning radioactive material into a dangerous weapon required expertise. Initially, the worst casualties would be the same as any bombing: people in the immediate blast vicinity would be annihilated by the explosion. Then iridium would be dispersed in a toxic cloud. Depending on wind speeds and other conditions, a huge area could be contaminated by gamma radiation. Few people would die initially, but over the long term anyone exposed was at risk of developing cancer or other genetic mutations. The area itself would be deemed uninhabitable, and the cleanup costs could be in the billions.

And that was what made a dirty bomb so effective. Called a “weapon of disruption,” as opposed to a weapon of mass destruction, the greatest danger would be from panic. If detonated in a major city, containment and decontamination of thousands of terrified victims would present an enormous challenge. Survivors of the blast might be trampled in the aftermath.

Transportation issues presented the largest impediment to unleashing a dirty bomb. Although the term “suitcase bomb” was coined after the Padilla case, unless a bomber used a specially lined container, he would probably die of severe radiation poisoning before reaching his target. And that container would be far too heavy to carry. Plus, they weren’t the sort of thing you ordered off eBay.

Judging by the preparations across the warehouse, Dante already had that covered. The other men were converting metal drums, lining them with overlapping sheets of alloys. Probably not enough to prevent all traces of radiation from leaking out, but it would stop detectors from going off at every firehouse and police station they passed. And once the bomb exploded, those metal sheets would turn into lethal shrapnel. Randall had to hand it to them, they’d thought of everything.