Minutes later, Redwood City reported back. A chest X-ray showed no deterioration of the lungs in any of the children. “The blood work showed traces of staphylococcal enterotoxin B.”

I watched Claire’s expression.

“What the hell does that mean?” Mayor Fiske demanded.

“It means they’ve got a severe staph infection,” she said, exhaling. “It’s serious, and it’s contagious, but it’s not ricin.”

The Rincon Center was full at noon. Hundreds of people chatting over lunch, scanning the sports pages, rushing around with bags from the Gap or Office Max. Just relaxing under the enormous plane of water that fell from the glittering roof.

The pianist was playing. Mariah Carey. “A hero comes along …” But no one seemed to notice the music or the player. Hell, he was awful.

Robert sat reading the paper, his heart beating wildly. No more room for talk or argument, he kept thinking. No more waiting for change. Today he’d make his own. God knows, he was one of the disenfranchised. In and out of VA hospitals. Made crazy by his combat experience, then abandoned. That was what had made him a radical.

He tapped the leather briefcase with his shoes, just to make sure it was still there. He was reminded of something he had seen on TV, in a dramatization of the Civil War. A runaway slave had been freed and then conscripted to fight for the North. He fought in some of the bloodiest battles of the war. After one, he happened to spot his old master, shell-shocked and wounded among the Confederate prisoners. “Hello, massa,” the slave went up to him and said, “looks like bottom rail’s on top now.”

And that’s what Robert was thinking as he panned the unsuspecting lawyers and bankers slopping down their lunch. Bottom rail’s on top now…

Across the crowd, the man Robert was waiting for stepped into the concourse—the man with the salt-and-pepper hair. His blood came alive. He stood, wrapping his fingers around the case handle, keeping his eyes fixed on the man—his target for today.

This was the moment, he told himself, when all the fancy speeches and vows and homilies turn into deed. He tossed down his newspaper. The area around the fountain was jam-packed. He headed toward the piano.

Are you afraid to act? Are you afraid to set the wheel in motion?

No, Robert said, I’m ready. I’ve been ready for years.

He stopped and waited at the piano. The pianist started up a new tune, the Beatles: “Something.” More of the white man’s garbage.

Robert smiled at the young red-headed dude behind the keyboard. He took a bill out of his wallet and stuffed it in the bowl.

Thanks, man, the pianist nodded.

Robert nodded back, almost laughed at the false camaraderie, and rested his briefcase against a leg of the piano. He checked the progress of his target—thirty feet away—and casually kicked the briefcase underneath the piano. Take that, you sons of bitches!

Robert started to drift slowly toward the north entrance. This is it, baby. This is what he’d been waiting for. He fumbled through his pocket for the stolen cell phone. The target was only about fifteen feet away. Robert turned at the exit doors and took it all in.

The man with the salt-and-pepper hair stopped at the piano, just as the Professor said he would. He took a dollar bill out of his wallet. Behind him, the eighty-foot column of water splashed down from the ceiling.

Robert pushed through the doors, walked away from the building, and depressed two preassigned keys on the cell phone—G-8.

Then the whole world seemed to burst into smoke and flame, and Robert felt the most incredible satisfaction of his entire life. This was a war he wanted to fight in.

He never saw the flash, only the building wrenching in a rumble of concrete and glass, doors blowing out behind him.

Start the revolution, baby… Robert smiled to himself. Bottom rail’s on top now…

There was a loud shout in the Emergency Command Center. One of the guys manning the police frequency yanked off his headset. “A bomb just went off at the Rincon Center!”

I turned to Claire and felt the life deflate out of me. The Rincon Center was one of the city’s most spectacular settings, in the heart of the Financial District, home to government agencies, business offices, and hundreds of apartments. This time of day, it would be jammed. How many people had just died?

I wasn’t waiting around for police reports to call in the damage or casualties. I ran out of the Emergency Command Center with Claire a step behind. We hopped in her medical examiner’s van. It took about fifteen minutes for us to race downtown and fight our way through the maze of traffic, fire vehicles, and bystanders crowded around the stricken area.

Reports coming over the radio said the bomb had gone off in the atrium, where it would be busiest at noon.

We ditched the van at the corner of Beale and Folsom and started to run. We could see smoke rising from the Rincon a couple of blocks away. We had to go to the Steuart Street entrance, running past the Red Herring, Harbor Court Hotel, the Y.

“Lindsay, this is so bad, so bad,” Claire moaned.

The first thing that hit me was the blunt cordite smell. The outside glass doors were completely blown away. People sat on the sidewalk, coughing, bleeding, slashed by exploding glass, expelling smoke out of their lungs. Survivors were still being evacuated left and right. That meant the worst was inside.

I took a deep breath. “Let’s go. Be careful, Claire.”

Everything was covered with hot black soot. Smoke stabbed at my lungs. The police were trying to clear some space. Fire crews were dousing sporadic blazes.

Claire knelt next to a woman whose face was burned and who was shouting that she couldn’t see. I pushed past them, farther in. A couple of bodies were crumpled in the center of the atrium near the Rain Column, which continued to pour water into a pond built into the floor. What have these people done? Is this their idea of war?

Experienced cops were barking into handheld radios, but I saw younger ones just standing around, blinking back tears.

In the center of the atrium, my eye fell on a mangle of twisted wood and melted wire—the remains of what looked like a piano. I spotted Niko Magitakos from the Bomb Squad crouched next to it. He had a look on his face that I will never forget. Something terrible like this, you pray it will never come.

I pushed my way over to Niko.

“The blast site,” he said, tossing a piece of charred wood in the piano pile. “Those bastards, those bastards, Lindsay. People were just having lunch here.”

I was no bomb expert, but I could see a ring of devastation—benches, trees, burn smears—the location of the casualties blasted out from the center of the atrium.

“Two witnesses say they saw a well-dressed black male. He left a briefcase under the piano and then split. My guess, it’s the same work as the Marina case. C-4, detonated electronically. Maybe by phone.”

A woman in a Bomb Squad jacket came running up, holding what looked like a fragment from a blown-apart leather case.

“Mark it,” Niko instructed her. “If we can find the handle, maybe there’ll even be a print.”

“Wait,” I said as she started to walk away. What she had found was a wide leather strap, the piece that closed over the top of a briefcase and buckled into the clasp. Two gold letters were monogrammed into the strap. AS.

A sickening feeling rose up inside me. They were fucking with us. They were mocking us. I knew what the letters stood for, of course.

A.S. August Spies. My cell phone went off and I grabbed it. Cindy was on the line. “Are you there, Lindsay?” she asked. “Are you okay?”

“I’m here. What’s up?”

“They took credit for the bombing,” she told me. “Somebody called it in to the paper. The caller said he was August Spies. He said, ‘Three more days, then watch out!’ He said this was just practice.”