"for the President," he said with a Spanish accent.

A postal service employee signed in the package and the time. He looked up and said. "Still raining?"

"More like a fine spray."

"Just enough to make life miserable."

"And slow traffic," the deliveryman said with a sour face.

"Have a good day anyway."

"You too."

The deliveryman left as the postal worker took the package and ran it under the fluoroscope. He stood back and stared at the screen as the X-rays revealed the object under the wrapping.

He easily identified it as a briefcase, but the picture puzzled him.

There was no indication of files or papers inside, no hard object with a distinguishing outline, nothing that looked like explosives. He was an old hand at X-ray identification, but the contents of the case threw him.

He picked up the phone and made a request to the person on the other end. Less than two minutes later a security agent appeared with a dog.

"Got one for Sweet-pea?" asked the agent.

The postal worker nodded as he set the package on the floor. "Can't make an I.D. on the scope."

Sweet-pea hardly resembled her namesake. She was a mutt, the result of a brief affair between a beagle and a dachshund. Huge brown eyes, a fat little body supported by short spindly legs, Sweet-pea was highly trained to sniff out every explosive from the common to the exotic. As the two men watched, she waddled around the package, nose quivering like a plump dowager sniffing at a perfume counter.

Suddenly she stiffened, the hair on her neck and back stood up, and she began backing away. Her face took on an odd, suspicious kind of distasteful expression, and she began to growl.

The agent looked surprised. "That's not her usual reaction."

"There's something weird in there," said the postal worker.

"Who is the package addressed to?"

"The President."

The agent walked over and punched a number on the phone. "We better get Jim Gerhart down here."

Gerhart, Special Agent in Charge of Physical Security for the White House, took the call during a brief lunch at his desk and left immediately for the mail reception room.

He observed the dog's reaction and eyebafled the package under the fluoroscope. "I don't detect any wiring or detonation device," he said in a Georgia drawl.

"Not a bomb," the postal worker agreed.

"Okay, let's open it."

The red silk wrapper was carefully removed, revealing a black leather attache case. There were no markings, not even a manufacturer's name or model number. Instead of a combination lock, both latches had inserts for a key.

Gerhart tried the latches simultaneously. They both unsnapped.

"The moment of truth," he said with a cautious gun.

He placed his hands on each corner of the upper lid and slowly lifted until the case was open and the contents in view.

"Jesus!" Gerhart gasped The security agent's face went white and he turned away.

The postal worker made gagging noises and staggered for the lavatory.

Gerhart slammed the lid shut. "Get this thing over to George Washington University Hospital."

The security agent couldn't reply until he swallowed the acid-tasting bile that had risen in his throat. Finally he coughed, "Is that thing real or is this some kind of Halloween trick or treat?"

"It's genuine," said Gerhart grin-dy- "And believe you me, it ain't no treat."

In his White House office, Dale Nichols settled back in his swivel chair and adjusted his reading glasses. for perhaps the tenth time he began scrutinizing the contents of a folder routed to him by Arrnando L6pez, the President's Senior Director Of Latin American Affairs.

Nichols gave off the image of a university professor, which indeed he had been when the President persuaded him to switch his sedate campus classroom at Stanford for the political cesspool of Washington. His initial reluctance had turned to amazement when he discovered he had a hidden talent for manipulating the White House bureaucracy.

His thicket of coffee-brown hair was parted neatly down the middle. His old-style spectacles, with small round lenses and thin wire frames, reflected a plodding temperament, a neversay-die type who was oblivious to everything but his immediate project. And, finally, the ultimate in academic clichds, the bow tie and the pipe.

He lit the pipe without removing his eyes from the articles clipped from Mexican newspapers and magazines dealing with only one subject.

Topiltzin.

Included were interviews granted by the charismatic messiah to officials who represented Central and South American countries. But he had refused to talk to American journalists or government representatives and none had penetrated his army of bodyguards.

Nichols had learned Spanish during a two-year tour in Peru for the Peace Corps, and easily read the stories. He took a legal pad and began making a list of claims and statements that came to light during the interviews.

1. Topiltzin describes himself as a man who came from the poorest of the poor, born in a cardboard shack on the edge of Mexico City's sprawling garbage dump, with no idea of the day, month or year. Somehow he survived and learned what it was to live amid the stink and flies and manure and muck of the hungry and homeless.

2. Admits to no schooling. History from childhood, until his emergence as a self-styled high priest of archaic TolteclAztec religion, is blank.

3. Claims to be the reincarnation of Topiltzin, tenthcentury ruler of the Toltecs, who was identified with the legendary god Quetzalcoatl.

4. Political philosophy a crazy blend of ancient culture and religion with vague sort of autocratic, one-man, noparty rule. Intends to play benevolent father role to Mexican people. Ignores questions on how he intends to revive shattered economy. Refuses to discuss how he will restructure government if he comes to power.

5. Spellbinding orator. Has uncanny rapport with his audience. Speaks only in old Aztec tongue through interpreters. Language still used by many Indians of Central Mexico.

6. Mainstream supporters are fanatical. His popularity has swept the country like the proverbial tidal wave. Political analysts predict he could will a national election by nearly six percentage points. Yet he refuses to participate in free elections, claiming, and rightly so, that corrupt leaders would never surrender the government after a losing campaign. Topiltzin expects to take over the country by public acclaim.

Nichols set his pipe in an ashtray, stared at the ceiling thoughtfully for a few moments, and began writing again.

SUMMARY: Topiltzin is either incredibly ignorant or incredibly gifted.

Ignorant if he is what he says he is.

Gifted if he has a method to his madness, a goat only he can see.

Trouble, trouble, trouble.

Nichols was going over the articles again, searching for a key to Topiltzin's character, when his phone buzzed. He picked up the receiver.

"the President on one," announced his secretary.

Nichols punched the button. "Yes, Mr. President."

"any news of Guy Rivas?"

"No, nothing."

There was a pause on the President's end. Then, finally, "He was scheduled to meet with me two hours ago. I'm concerned. If he Encountered a problem, his pilot should have sent us word by now."

"He didn't fly to Mexico City in a White House jet," explained Nichols.