When they jostled the doctor's shoulders, making him feel threatened and claustrophobic, he moved toward the back of the compartment, still clutching his satchel. At the rearmost window, the view was blocked by guy cables and the sweep of the dirigible's nearest fin. The seal of vulcanized rubber did not fit perfectly around the pane of glass, allowing a chill draft. Vargas huddled in his tweed suit, glad for the brief solitude, anxious to be off the zeppelin.

Fidgeting, he swiped a handkerchief across his brow as he discreetly eyed the room. When he was sure none of the passengers were paying any attention to him, Vargas reached into his pocket and withdrew two small test tubes.

Swallowing hard, thinking of all the work and all the dark memories that had thrown him into this dangerous situation, he let his gaze linger on the twin vials before he wrapped them in the soft folds of his handkerchief. He snapped open his satchel and placed them protectively inside.

The loudspeaker system crackled, and the captain's voice boomed out in deep, rolling German. Vargas flinched in instinctive terror, remembering other harsh commands delivered over blaring intercoms.

But the man was simply announcing the Hindenburg lII's imminent arrival. "All passengers please take your seats and prepare for the docking procedure. We may encounter some slight turbulence due to the snowstorm as we dock to the Empire State Building."

Outside, louder than the thrumming of the zeppelin's impressive motors, came the drone of airplane engines. Six swift fighter aircraft, each one painted with intimidating insignia — tiger stripes, leopard spots, or a red mouth of snarling fangs — roared past the gliding Hindenburg.

Vargas quailed, but the other passengers whistled and cheered. The six aircraft sped past, tilting their wings in friendly acknowledgment. The captain came back over the loudspeaker. "Ladies and gentlemen, we are fortunate to receive a ceremonial escort from the famous Flying Legion! If any of you had doubts that we would arrive safely, I trust they are now put to rest?"