"Michael Petersen?"

The renowned biochemist and Nobel laureate activated the door-open remote on the silver Mercedes sedan and set his briefcase down on the garage pavement, ignoring the voice behind him. It was well past midnight, and he had just worked seventeen hours straight. Exhausted and bleary-eyed, Petersen wanted nothing more than to get home, slip into his pajamas, snuggle next to his wife and sleep. He was not interested in conversations, especially not in the ChemGen underground garage.

"Doctor?" the man asked again, sounding concerned.

"What is it?" Petersen replied as he opened the car door. He saw a reflection in the tinted glass; a man was standing close behind him. Too close. Petersen turned abruptly.

"These are for you," the man said, handing Petersen an unwrapped bouquet of flowers.

The man was smartly dressed in a light tan coat, white shirt and dark slacks. Certainly not a mugger. Petersen did not recognize him.

"For whatever for?" Petersen asked, but taking the gift. He noticed that his lips began to tingle as he grasped the arrangement of snapdragons, delphinium and liatris. Allergies, he thought. And while any other person would have thought it odd to be presented with such a gesture at such an hour, for the acclaimed biochemist who once was named by Time magazine as the "father of cellulose endochronology" for his work on plant genetics, Petersen was accustomed to such random acts of interruption and tokens of recognition. Usually it was a pushy member of the media angling for a story, or a wide-eyed aspiring student wishing to press the flesh of one of the world's foremost authorities in pharmaceutical research.

But the man before him was neither.

"In gratitude for your service to the profession," the man replied.

Petersen coughed. "Since when does FTD deliver to parking lots at midnight?" he grunted, staring back at the man.

Something wasn't right.

Then he noticed it.

The man was wearing thick rubber gloves.

"What is this all about?" Petersen asked, raising his voice, irritated.

But the man did not answer; he simply stood there, watching Petersen.

As if waiting.

Suddenly Petersen's throat began to swell. He coughed, and felt a sharp pain in his chest. His tongue began to engorge, as did his entire mouth and throat, closing off his windpipe.

"What in God's name..." he coughed again, grabbing his throat. As a trained physician with a Stanford Ph.D. in both biology and genetics, he recognized the sensations immediately. After the chest pains and the shortness of breath, he would experience a severe flushing of the skin, then nausea, then his heart rate would rise and his blood pressure would collapse. It happened once before, when he ate peanuts as a child.

Only this time it was much, much faster.

"Anaphylaxis!" he exclaimed. "But how?"

The man smiled. "Not how...but why," he said calmly. "But you know, don't you Petersen? You've known all along."

Petersen dropped the bouquet on the concrete and looked down at his hands.

It was the flowers; the allergen was in the flowers!

"It cannot come to this! They gave their word!" Petersen shouted, his voice muffled by internal swelling. He clutched at his chest; he felt the beginnings of a heart attack, a seizure induced by his immune system over-reacting and releasing copious amounts of histamine and other chemicals into his bloodstream.

"So did you, doctor. You knew the consequences...and you knew you needed to keep quiet. You took an oath, an oath that you have violated." The man squinted, like a doctor carefully monitoring a patient, then looked at his watch.

"How long?" Petersen asked, now choking. "How long before I die?"