lt;p>Dan Brown is the author of The Da Vinci Code, one of the most widely read novels of all time, as well as the international bestsellers Angels & Demons, Deception Point, and Digital Fortress.  He lives in New England with his wife.

PrologueHouse of the Temple8:33 P.M. The secret is how to die.

Since the beginning of time, the secret had always been how to die.

The thirty-four-year-old initiate gazed down at the human skull cradled in his palms. The skull was hollow, like a bowl, filled with bloodred wine.Drink it, he told himself. You have nothing to fear. As was tradition, he had begun this journey adorned in the ritualistic garb of a medieval heretic being led to the gallows, his loose-fitting shirt gaping open to reveal his pale chest, his left pant leg rolled up to the knee, and his right sleeve rolled up to the elbow. Around his neck hung a heavy rope noose a "cable-tow" as the brethren called it. Tonight, however, like the brethren bearing witness, he was dressed as a master.The assembly of brothers encircling him all were adorned in their full regalia of lambskin aprons, sashes, and white gloves. Around their necks hung ceremonial jewels that glistened like ghostly eyes in the muted light. Many of these men held powerful stations in life, and yet the initiate knew their worldly ranks meant nothing within these walls. Here all men were equals, sworn brothers sharing a mystical bond.As he surveyed the daunting assembly, the initiate wondered who on the outside would ever believe that this collection of men would assemble in one place . . . much less this place. The room looked like a holy sanctuary from the ancient world.The truth, however, was stranger still.I am just blocks away from the White House.This colossal edifice, located at 1733 Sixteenth Street NW in Washington, D.C., was a replica of a pre-Christian temple the temple of King Mausolus, the original mausoleum . . . a place to be taken after death. Outside the main entrance, two seventeen-ton sphinxes guarded the bronze doors. The interior was an ornate labyrinth of ritualistic chambers, halls, sealed vaults, libraries, and even a hollow wall that held the remains of two human bodies. The initiate had been told every room in this building held a secret, and yet he knew no room held deeper secrets than the gigantic chamber in which he was currently kneeling with a skull cradled in his palms.The Temple Room.This room was a perfect square. And cavernous. The ceiling soared an astonishing one hundred feet overhead, supported by monolithic columns of green granite. A tiered gallery of dark Russian walnut seats with hand-tooled pigskin encircled the room. A thirty-three-foot-tall throne dominated the western wall, with a concealed pipe organ opposite it. The walls were a kaleidoscope of ancient symbols . . . Egyptian, Hebraic, astronomical, alchemical, and others yet unknown.Tonight, the Temple Room was lit by a series of precisely arranged candles. Their dim glow was aided only by a pale shaft of moonlight that filtered down through the expansive oculus in the ceiling and illuminated the room's most startling feature an enormous altar hewn from a solid block of polished Belgian black marble, situated dead center of the square chamber.The secret is how to die, the initiate reminded himself."It is time," a voice whispered.The initiate let his gaze climb the distinguished white-robed figure standing before him. The Supreme Worshipful Master. The man, in his late fifties, was an American icon, well loved, robust, and incalculably wealthy. His once-dark hair was turning silver, and his famous visage reflected a lifetime of power and a vigorous intellect."Take the oath," the Worshipful Master said, his voice soft like falling snow. "Complete your journey."The initiate's journey, like all such journeys, had begun at the first degree. On that night, in a ritual similar to this one, the Worshipful Master had blindfolded him with a velvet hoodwink and pressed a ceremonial dagger to his bare chest, demanding: "Do you seriously declare on your honor, uninfluenced by mercenary or any other unworthy motiv