Agent Vance quietly gathered the salvaged sheets, sliding them between dry napkins and stowing the damp remnants into her leather jacket.

"That was a confirmation signal," Agent Vance murmured. "The transfer hasn't happened yet. They're waiting for the cabin lights to dim after the main meal service when passenger movement is minimal and the crew is clearing trays."

Elena swallowed hard, looking toward the curtain that led back to the main galley. The cabin was calm, wrapped in the artificial tranquility of long-distance flight, yet beneath the surface, a lethal transaction was unfolding between the rows.

"What do we do now?" Elena asked, her voice steadying as the initial panic gave way to resolved focus.

"Now, Flight Attendant Vance, we finish your beverage service," Agent Vance replied, a faint, dangerous shadow of a smile touching the corner of her lips. "You are going to take a fresh cart down the starboard aisle. You will serve seat 4K his requested silence, and while you do, you will confirm whether his carry-on remains in the overhead bin or beneath his feet. We have two hours before London air traffic control initiates our descent vectors. Let us make sure our guests find their reception waiting."

Chapter 6: The Observation Walk

The hum of the twin General Electric turbofans was a steady, low-frequency drone that rattled the glassware inside the service cart. At thirty-seven thousand feet, the cabin of Flight 884 was suspended in an artificial twilight, the overhead panels dimmed to simulate a restful dusk while the late-afternoon sun still sheared against the cloud tops outside.

Elena adjusted the cuff of her navy blazer, checking the alignment of her silver name badge before releasing the footbrake on the heavy aluminum cart. Her posture was the product of six years of transatlantic service: spine erect, shoulders relaxed, chin level, and a warm, practiced neutral smile firmly in place. To any onlooker in the Boeing 777’s forward cabin, she was merely commencing the mid-flight refresher service.

Underneath the practiced facade, her senses were tuned to every twitch of fabric and shift in weight along the starboard corridor.

She nudged the cart forward, its rubberized casters gliding softly over the plush carpet. Her first mark sat in 4K: Klaus Richter, traveling under the forged identity of David Sterling, an international commodities broker with a spotless digital footprint and a tailored charcoal sports coat that concealed far too much tension.

"Still doing well with the sparkling water, sir?" Elena asked softly as she halted the cart just forward of row 4, leaning in with practiced deference.

Richter did not immediately look up from his tablet. His fingers hovered over the screen for a fractional second—long enough for Elena to catalog the slight tremor in his right index finger before he locked it flat.

"I am fine, thank you," Richter murmured, his accent impeccably clipped, scrubbed clean of any Germanic cadence.

"Of course. Let me know if you change your mind," Elena replied, keeping her voice light.

Her gaze swept downward, masking her intent behind a sweep of the linen cloth across the cart's brushed metal surface. Stowed precisely beneath seat 4K, pulled flush against the seat stanchion, was an olive-drab ballistic nylon duffel. It was not positioned casually. The zippered access faced outward, unobstructed by footrests, and the pull-tab had been tucked into an elastic loop—a signature habit of individuals trained to access equipment rapidly without generating rustling noises.

Elena reached down to offer a refill to the passenger in 4H, angling her body so her peripheral vision encompassed seat 3B across the narrow dividing aisle.

The occupant of 3B—a gaunt man registered as Marcus Lind—sat stiffly under a thin fleece blanket despite the cabin temperature resting comfortably at twenty-two degrees. Lind was not reading, nor was he watching the entertainment screen. His eyes remained fixed on the reflection in the dark polycarbonate window of the forward bulkhead.

As Elena leaned across the cart, Richter’s left hand dropped from the armrest.

It was a micro-gesture: two subtle taps of the knuckle against the outer composite shell of seat pod 4K, followed by a slight curl of the thumb toward the cabin center.

In the reflection across the aisle, Lind responded almost instantly. His throat muscles tightened in a dry swallow; his right shoulder dropped half an inch, aligning his torso with the aisle gap.

Signal acknowledged, Elena thought, the adrenaline prickling the back of her neck. The transfer window is opening.

She smoothly engaged the cart brake, offered a soft nod to an elderly passenger across the aisle, and maintained her steady, rhythmic glide toward the forward galley. Every protocol had to appear inviolable; the slightest misstep would cause Richter to retract into his shell before the package ever surfaced.

Chapter 7: Silent Signals

In seat 2C, Agent Eleanor Vance had not moved for nearly forty minutes. To the casual eye, she was an exhausted corporate attorney sleeping off a red-eye flight, her wool travel wrap pulled up to her collarbone and a silk sleep mask pushed up onto her forehead like a headband. But Vance’s dark eyes were sharp, tracking the shadows cast by the overhead reading lights.