"It's apples and G.o.dd.a.m.n oranges," Jabba said."We've got gamma rays against electromagnetic pulse.Fissionable against unfissionable. Some is pure. Some ispercentage. It's a mess!"

"It's got to be here," Susan said firmly."We've got to think. There's some difference betweenplutonium and uranium that we're missing! Somethingsimple!"

"Ah ... guys?" Soshi said. She'd created asecond doc.u.ment window and was perusing the rest of the Outlaw Labsdoc.u.ment.

"What is it?" Fontaine demanded. "Findsomething?"

"Um, sort of." She sounded uneasy. "You know howI told you the Nagasaki bomb was a plutonium bomb?"

"Yeah," they all replied in unison.

"Well ..." Soshi took a deep breath. "Lookslike I made a mistake."

"What!" Jabba choked. "We've been lookingfor the wrong thing?"

Soshi pointed to the screen. They huddled around and read thetext: ... the common misconception that the Nagasaki bomb was aplutonium bomb. In fact, the device employed uranium, like itssister bomb in Hiroshima.

"But-" Susan gasped. "If both elements wereuranium, how are we supposed to find the difference between thetwo?"

"Maybe Tankado made a mistake," Fontaine ventured."Maybe he didn't know the bombs were the same."

"No." Susan sighed. "He was a cripple because ofthose bombs. He'd know the facts cold."

CHAPTER 126

"One minute!"

Jabba eyed the VR. "PEM authorization's going fast.Last line of defense. And there's a crowd at thedoor."

"Focus!" Fontaine commanded.

Soshi sat in front of the Web browser and read aloud.

... Nagasaki bomb did not use plutonium but rather anartificially manufactured, neutron-saturated isotope of uranium238."

"d.a.m.n!" Brinkerhoff swore. "Both bombs useduranium. The elements responsible for Hiroshima and Nagasaki wereboth uranium. There is no difference!"

"We're dead," Midge moaned.

"Wait," Susan said. "Read that last partagain!"

Soshi repeated the text. "... artificially manufactured,neutron-saturated isotope of uranium 238."

"238?" Susan exclaimed. "Didn't we just seesomething that said Hiroshima's bomb used some other isotopeof uranium?"

They all exchanged puzzled glances. Soshi frantically scrolledbackward and found the spot. "Yes! It says here thatthe Hiroshima bomb used a different isotope of uranium!"

Midge gasped in amazement. "They're bothuranium-but they're different kinds!"

"Both uranium?" Jabba muscled in and stared at theterminal. "Apples and apples!

Perfect!"

"How are the two isotopes different?" Fontainedemanded. "It's got to be something basic."

Soshi scrolled through the doc.u.ment. "Hold on ... looking... okay ..."

"Forty-five seconds!" a voice called out. Susan looked up. The final shield was almost invisible now.

"Here it is!" Soshi exclaimed.

"Read it!" Jabba was sweating. "What's thedifference! There must be some difference between thetwo!"

"Yes!" Soshi pointed to her monitor."Look!"

They all read the text:

... two bombs employed two different fuels ... preciselyidentical chemical characteristics. No ordinary chemical extractioncan separate the two isotopes. They are, with the exception ofminute differences in weight, perfectly identical.

"Atomic weight!" Jabba said, excitedly."That's it! The only difference is their weights!That's the key! Give me their weights! We'll subtractthem!"

"Hold on," Soshi said, scrolling ahead. "Almostthere! Yes!" Everyone scanned the text.

... difference in weight very slight ...

... gaseous diffusion to separate them ...

... 10,032498X10134 as compared to19,39484X1023.**

"There they are!" Jabba screamed. "That'sit! Those are the weights!"

"Thirty seconds!"

"Go," Fontaine whispered. "Subtract them.Quickly."

Jabba palmed his calculator and started entering numbers.

"What's the asterisk?" Susan demanded."There's an asterisk after the figures!"

Jabba ignored her. He was already working his calculator keysfuriously.

"Careful!" Soshi urged. "We need an exactfigure."

"The asterisk," Susan repeated. "There's afootnote." Soshi clicked to the bottom of the paragraph.

Susan read the asterisked footnote. She went white. "Oh . .. dear G.o.d."

Jabba looked up. "What?"

They all leaned in, and there was a communal sigh of defeat. Thetiny footnote read: **12% margin of error. Published figures vary from lab tolab.

CHAPTER 127

There was a sudden and reverent silence among the group on thepodium. It was as if they were watching an eclipse or volcaniceruption-an incredible chain of events over which they had nocontrol. Time seemed to slow to a crawl.

"We're losing it!" a technician cried."Tie-ins! All lines!"

On the far-left screen, David and Agents Smith and Colianderstared blankly into their camera. On the VR, the final fire wallwas only a sliver. A ma.s.s of blackness surrounded it, hundreds oflines waiting to tie in. To the right of that was Tankado.

Thestilted clips of his final moments ran by in an endless loop. Thelook of desperation-fingers stretched outward, the ringglistening in the sun.

Susan watched the clip as it went in and out of focus. Shestared at Tankado's eyes- they seemed filled with regret.He never wanted it to go this far, she told herself.

Hewanted to save us. And yet, over and over, Tankado held hisfingers outward, forcing the ring in front of people's eyes.He was trying to speak but could not. He just kept thrusting hisfingers forward.

In Seville, Becker's mind still turned it over and over. Hemumbled to himself, "What did they say those two isotopeswere? U238 and U ...?" He sighed heavily-it didn'tmatter. He was a language teacher, not a physicist.

"Incoming lines preparing to authenticate!"

"Jesus!" Jabba bellowed in frustration. "How dothe d.a.m.n isotopes differ? n.o.body knows how the h.e.l.lthey're different?!" There was no response. The room fullof technicians stood helplessly watching the VR. Jabba spun back tothe monitor and threw up his arms. "Where's a nuclearf.u.c.king physicist when you need one!" * * *

Susan stared up at the QuickTime clip on the wall screen andknew it was over. In slow motion, she watched Tankado dying overand over. He was trying to speak, choking on his words, holding outhis deformed hand ... trying to communicate something. He wastrying to save the databank, Susan told herself. Butwe'll never know how.

"Company at the door!"

Jabba stared at the screen. "Here we go!" Sweat poureddown his face.

On the center screen, the final wisp of the last firewall hadall but disappeared. The black ma.s.s of lines surrounding the corewas opaque and pulsating. Midge turned away. Fontaine stood rigid,eyes front. Brinkerhoff looked like he was about to get sick.

"Ten seconds!"

Susan's eyes never left Tankado's image. Thedesperation. The regret. His hand reached out, over and over, ringglistening, deformed fingers arched crookedly in stranger'sfaces. He's telling them something. What is it?

On the screen overhead, David looked deep in thought."Difference," he kept muttering to himself."Difference between U238 and U235. It's got to besomething simple."

A technician began the countdown. "Five! Four!Three!"

The word made it to Spain in just under a tenth of a second. Three ... three.

It was as if David Becker had been hit by the stun gun all overagain. His world slowed to stop. Three ... three ... three.238 minus 235! The difference is three! In slow motion, hereached for the microphone ...

At that very instant, Susan was staring at Tankado'soutstretched hand. Suddenly, she saw past the ring ... past theengraved gold to the flesh beneath ... to his fingers.

Three fingers. It was not the ring at all. It was the flesh.Tankado was not telling them, he was showing them. He was tellinghis secret, revealing the kill-code-begging someone tounderstand ... praying his secret would find its way to the NSAin time.

"Three," Susan whispered, stunned.

"Three!" Becker yelled from Spain.

But in the chaos, no one seemed to hear.

"We're down!" a technician yelled. The VR began flashing wildly as the core succ.u.mbed to a deluge.Sirens erupted overhead.

"Outbound data!"

"High-speed tie-ins in all sectors!"

Susan moved as if through a dream. She spun toward Jabba'skeyboard. As she turned, her gaze fixed on her fiance, DavidBecker. Again his voice exploded overhead.

"Three! The difference between 235 and 238 isthree!"

Everyone in the room looked up.

"Three!" Susan shouted over the deafeningcacophony of sirens and technicians. She pointed to the screen. Alleyes followed, to Tankado's hand, outstretched, three fingerswaving desperately in the Sevillian sun.

Jabba went rigid. "Oh my G.o.d!" He suddenly realizedthe crippled genius had been giving them the answer all thetime.

"Three's prime!" Soshi blurted."Three's a prime number!"

Fontaine looked dazed. "Can it be that simple?"