Thinking he was about to be frisked, Phillipo complied without protest. Francesca's warning came too late. The pistol barrel arced down in a silvery blur and struck the bodyguard above the right ear. The sickening crunch was drowned out by the bodyguard's cry of pain as he doubled over and crumpled onto the floor.

Francesca jumped up from her seat. "Why did you do that?" she said defiantly. "You have his gun. He couldn't harm you."

"Sorry, miss. I'm a firm believer in insurance." Riordan stepped over the prostrate form in the aisle as if it were a sack of potatoes. "Nothing like a cracked skull to discourage a man from getting into trouble. There's a first aid kit up there on the wall. Taking care of him should keep you busy 'til it's time to set down." He tipped his hand to his cap, strolled back to the cockpit, and shut the door.

Francesca knelt by the stricken bodyguard. She soaked cloth napkins in mineral water and cleaned the wound, then applied pressure until the bleeding was stanched. She daubed an antiseptic on the scalp cut and the bruised skin around it, wrapped ice in another napkin, and pressed it to the side of the man's head to prevent swelling.

As Francesca sat by his side, she tried to piece the puzzle together. She ruled out a kidnapping for money. The only reason someone would go through this much trouble would be for her process. Whoever was behind this mad scheme wanted more than a scale model and the papers explaining her work. They could have broken into the lab or grabbed her luggage at the airport. But they needed Francesca to interpret her findings. Her process was so arcane, so different, that it didn't conform to the norms of science, which is why no one had thought of it before.

The whole thing didn't make sense! Within a day or two she was going to give the process to the countries of the world for nothing. No patents. No copyright. No royalty fees. Absolutely free of charge. Anger smoldered in her breast. These ruthless people were stopping her from improving the lot of millions.

Phillipo groaned. He was coming around. His eyes blinked open and came into focus.

"Are you all right?" she said.

"It hurts like the devil, so I must be alive. Help me sit up, please."

Francesca put her arm around Phillipo and lifted until he sat with his back against a seat. She unscrewed a bottle of rum from the bar and put it to his lips. He sipped some liquor, managed to keep it down, then took a healthy swallow. He sat there for a moment waiting to see if his guts would come up. When he didn't vomit, he smiled. "I'll be fine. Thank you."

She handed him his glasses. "I'm afraid they were broken when he hit you."

He tossed them aside. "They are only plain glass. I can see fine without them." The level eyes that bored into Francesca were not those of a frightened man. He glanced at the closed cockpit door. "How long have I been out?"

"Twenty minutes, maybe."

"Good, there is still time."

"Time for what?"

His hand slid down to his ankle and came up filled with a snub-nosed revolver.

"If our friend hadn't been so anxious to give me a headache, he would have found this," he said with a grim smile.

This was definitely not the same rumpled man who had seemed more like an absentminded professor than a bodyguard. Francesca's elation was tempered by reality. "What can you do? They have at least two guns, and we can't fly the plane."

"Forgive me, Senhora Cabral. Another failure to be forthright on my part." Sounding almost guilty, he said, "I forgot to mention that I was in the Brazilian air force before I joined the secret service. Please help me up."

Francesca was speechless. What other rabbits would this man pull out of his hat? She gave him a hand until he was able to stand on shaky legs. After a minute a new strength and determination seemed to flow through his body. "Stay here until I tell you what to do," he said with the air of a man used to people obeying his command.

He went forward and opened the door. The pilot glanced over his shoulder and said, "Hey, look who's back from the land of the living dead. Guess I didn't hit you hard enough."

"You don't get a second chance," Phillipo said. He jammed the revolver barrel under the Texan's ear hard enough to hurt. "If I shoot one of you, the other can still fly. Which one will it be?"

"Christ, you said you took his gun!" Carlos said.

"You've got a short memory, cavaleiro," the pilot replied calmly. "You shoot us and who's going to fly the plane?"

"I will, cavaleiro. Sorry I didn't bring my pilot's license with me. You'll have to take my word for it."

Riordan turned his head slightly and saw the cold smile wreathing the bodyguard's face.

"I take back what I said about dealing with a professional," Riordan said. "What now, partner?"

"Give me the two guns. One at a time."

The pilot handed over his pistol and the one he had taken from Phillipo. The bodyguard passed the weapons back to Francesca, who had come up behind him.

"Get out of your seat," he ordered, backing into the cabin. "Slowly."

Riordan caught the copilot's eye and levered himself out of his seat. Using his body to shield the gesture, he made a quick palm-down flip with his hand. The copilot nodded almost imperceptibly to show he understood.

The pilot followed Phillipo as if drawn by an imaginary leash, as the bodyguard backed up into the cabin. "I want you to go lie facedown on the divan," Phillipo said, keeping his gun pointed at Riordan's chest.

"Hell, I was hoping I could take a nap," the pilot said. "That's real kind of you."

Francesca had backed off the aisle to make room for the two men to pass. Phillipo asked her to get some plastic trash bags from under a front seat. Phillipo intended to use the bags to bind the pilot. With Riordan on ice he would only have to deal with the copilot.

The cabin was about twelve feet long. In the tight space Phillipo had to step aside to let the other man pass. He re minded Riordan not to try anything at close quarters, because it would be impossible to miss. Riordan nodded and stepped to ward the rear. They were only a few inches apart when the co pilot put the plane over on its left side.

Riordan had expected the move, but he didn't know when it would come or that it would be so violent. He lost his balance and was thrown onto a seat, his head slamming into the bulkhead. Phillipo was lifted off his feet. He flew across the cabin and landed on top of Riordan.

The pilot disentangled his right hand and blasted his big fist into the bodyguard's jaw. Phillipo saw galaxies whirling over his head and almost blacked out, but he managed to keep a death grip on the gun. Riordan brought his arm back for another punch. Phillipo blocked it with his elbow.

Both men were street fighters. Phillipo clawed at Riordan's eyes. The pilot bit Phillipo on the fleshy part of the palm. The bodyguard jammed his knee into Riordan's groin, and when the pilot opened his mouth, Phillipo snapped his head forward, smashing the cartilage in Riordan's nose. He might have gained the upper hand, but at that point the copilot made the plane yaw sharply to the right.

The struggling men flew across the aisle into the opposite seat. Now the American was on top. Phillipo tried to club Riordan with the gun's muzzle, but the pilot grabbed his wrist with two hands and twisted it away and down. Phillipo was strong, but he was no match for the double-teamed assault. The barrel swung closer to his midsection.