Our best guess at the moment is that they killed the galley crew earlier in the day and took their places, using counterfeit Coast Guard identification and orders."

"Please continue your findings," Oates persisted.

"Then the abductors on the yacht," Emmett repeated, "untied the mooring lines, allowing the Eagle to drift silently from the pier to make room for its double. Polaski heard nothing from his post near the bank, because any strange sounds were covered by the hum of the engine-room generators. Then, once the bogus yacht was tied to the pier its crew, probably no more than two men, rowed a small dinghy to the Eagle and escaped with the others down river. One remained, however, to impersonate agent Brock.

By the time Polaski conversed with Brock's impersonator, the switch had already been made. At the next post change, the man calling himself Brock slipped off and joined the men operating the foggers.

Together they drove off and swung on the highway toward Alexandria. We know that much by footprints and tire tracks."

Everyone but Emmett focused his attention on the blackboard, as if trying to visualize the scene. The incredible timing, the ease with which presidential security was breached, the smoothness of the entire operation, staggered everyone.

"I can't help but admire the execution," General Metcalf said.

"They must have taken a long time to plan this thing."

"Our estimate is three years," said Emmett.

"Where could they possibly have found an identical boat?" Fawcett muttered to no one in particular.

"My investigating team considered that. They traced the old boating records and found that the original builder constructed the Eagle and a sister ship named the Samantha at the same time. The last registered owner of the Samantha was a stockbroker in Baltimore. He sold it about three years ago to a guy named Dunn.

That's all he could tell us. It was an under-the-table cash transaction to beat a profit tax. He never saw Dunn or the yacht again.

The Samantha that was never registered or licensed under the new owner.

They both dropped from sight."

"Was it identical in every respect to the Eagle?" Brogan asked.

"A creative job of deception. Every stick of furniture, bulkhead decor, paint and equipment is a perfect match."

Fawcett nervously tapped a pencil on the table. "How did you catch on?"

"Every time you enter and leave a room, you leave particles of your presence behind. Hair, dandruff, lint, fingerprints-they can all be detected. My lab people couldn't find one tiny hint that the President or the others had ever been on board."

Oates straightened in his chair. "The Bureau has done a magnificent job, Sam. We're all grateful."

Emmett gave a curt nod and sat down.

"The yacht transfer brings up a new angle," Oates continued.

"As gruesome as it sounds, we have to consider the possibility they were all assassinated."

"We've got to find the yacht," Mercier said grimly.

Emmett looked at him. "I've already ordered a surface and air search."