Travis broke out of his shock and thrust the microphone up to his mouth. “All units! All units! Something’s wrong. The enemy force is inside Central Control. Move in! Move in!” Then, without hope, he screamed into the mike once more. “Carlson! Answer me! Where are you?”

Eric poked his head around the door marked “Authorized Personnel Only” and looked across the Monitoring Room to where Nicole sat at one of the consoles. “Did you get the message off?”

“Yes, it’s sent. I repeated it three times. It should wake everyone in the city.”

“Good.” He pointed to the woman who lay on the carpeting. “You’d better drag her out of here. Take her far enough away that she won’t be hurt when this blows. Then see if you can find the unit locations for the Guardians. If we’re in a trap, let’s find out.”

Without waiting for a response, Eric went to the room where the rows of central processing units lined each wall and took clumps of reddish-gray putty from the sack. He was grateful they had found Don Brownley and Charles Metcalf, both excellent chemists. In the village they had been unable to make anything more complex than dynamite and gunpowder, but this plastic explosive, made by the two partners in Flathead Chemical and Fertilizer Company, was far more sophisticated and better suited for their task.

The plan was very simple. While Nicole stayed in the main room at the console, Eric, Rod, and Dick worked on the CPUs. Moving swiftly from computer to computer, Rod and Eric slapped the putty in large globs at the base of the machines. Then Dick, moving right behind them, inserted detonators into each glob, stringing a thin red electrical wire from patch to patch.

The detonating system was almost as simple as the plan. The heart of it was a small blue metal box with a red plastic button, much like a doorbell, only about three inches square. Andreason had wired both boxes—he had insisted on a back-up in case the first one malfunctioned—with two small flashlight batteries as the power source. A thick roll of electrical wire, long enough to stretch from the Monitoring Room out to the south fire exit, was connected to the clip at the edge of the blue box. From the other end of the wire dangled a small circuit board with a ten-second delay switch. Once connected to the wires leading from detonator to detonator, the circuit board required only one light push on the red button. The delay switch would activate, and ten seconds later a fury of explosive power would be unleashed. The device was simple, the results spectacular.

Almost a full minute later Eric heard Nicole cry, her voice muffled by the noise of the big units in the room. “I can’t get access to the Guardian code. Someone has changed it.”