“The air pressure is dropping rapidly,” Thorne said, his voice smooth and hypnotic.

“If we don’t dump the fuel and descend to ten thousand feet immediately, we will all suffer permanent brain damage.”

His hand hovered just inches from the fuel cutoff switches.

I noticed something then.

Thorne’s fingers were steady, but there was a faint smear of blue ink on his right wrist.

It looked exactly like the stamp on the shipping manifest I had signed in the galley before we left Boston.

The manifest for the medical supplies that had been loaded into the forward cargo hold.

Gerald, still sitting in the observer’s seat, looked from Thorne to the fuel switches.

The panic in Gerald’s eyes was changing, shifting from the mindless fear of suffocation to something else.

He looked at the silver canister in Thorne’s hand.

Then he looked at the smear of blue ink on the doctor’s wrist.

“Wait,” Gerald muttered, his voice trembling.

“You… you were in the forward galley right before the air went bad.”

“I was helping a passenger with motion sickness, Mr. Whitmore,” Thorne said, not breaking eye contact with me.