WE ARE halfway over the Coral Sea when I spot the burning gaze from across the aisle - quite a feat considering I have the window seat.
"What does he want?" I wonder.
"Who is he? Do I know those eyes from somewhere in Vanuatu?"
I'm not about to stare back.
Nothing good can come from making eye contact with strange men on public transport.
It is a mystery, and one that I have to work out.
Half-crazed with exhaustion, I replay the events of the past five days through my mind...
Barely a moment passed between touching down in Port Vila and my ascent up a mountain at the island's centre.
I had been told I would need all my wits to survive this "adventure holiday", but my limbs still buckled as I peered over the edge of the cascade.
"We're climbing down that?" I asked our instructor, a former IT worker from Australia who set up the island's first abseiling business.
He smiled and looked at his apprentice Grasshopper, so named because of his barefooted ability to bounce from rock to perilous rock.
We checked the ropes and launched off the waterfall, feeling its full force as it crashed upon us.
"I used to have a boring life in Australia," our instructor told me.
"Now I don't."
Day two brought us back to the airport, towing light packs and a healthy sense of trepidation.
We were bound for the island of Tanna, a land far removed from western civilisation and yet primed to become the Pacific's next major tourism hotspot.
Besides the shy, smiling people, the sun-kissed beaches and impenetrable jungles, Tanna has one major drawcard.
Mount Yasur is the world's most accessible active volcano - and I don't say that lightly.
After a 15-minute climb up a winding cement path, we were at the precipice.
Below us we could see the spectacular and terrifying inner-workings of the earth, a constant churning of hot lava and sulphur clouds that culminated in violent bursts every few minutes.
I was almost ready to start a volcano cult before we were called back to camp (actually beach-front bungalows with hot water and all the trimmings).
We slept by the crashing of the waves.
We woke for an early breakfast and our latest helping of adventure, this time by way of the ocean.
Onboard the dinghy, we headed a short way out until we found a towering cliff face at the water's edge.
Boat anchored, we dove in and swam towards the crag where an underwater opening would lead us to the Blue Cave.
Only a short free dive lay between us and the azure waters of the cavern.
We tread water and splash up a maelstrom of turquoises, cyans and ultramarines, all reflections from the clear sky through an overhead cavity.
Back at the dinghy, we primed ourselves for the item on the itinerary.
We were to meet a warrior tribe in the highlands of Tanna, to learn about their black magic and their former penchant for cannibalism.
Fortunately, they have had a change of heart in the years since they tried to eat the boot of a white missionary.
Their show was designed for tourists, but still terrifying as they took every opportunity to ambush visitors as they would have 150 years ago.
Fatigue had well and truly set in so, after sharing a cup of mouth-numbing kava, we left for dinner, a few wind-down beers and sleep.
Our final full day in Vanuatu brought us back to Port Vila, the political and economic capital of the island archipelago.
We were all set for some high-adrenaline fun - not exactly the most culturally-insightful activity, but entertaining nonetheless.
A four-wheel drive buggy tour through the jungle was just what we needed to round off this tour.
We celebrated our trip's end with one final flourish, a night on the town, which lasted longer than it should have.
That bout of nostalgia was fun, but it brings me no closer to discovering the identity of this mystery man across the aisle.
I can feel his eyes on me but my curiosity does not reach boiling point until we're waiting at the baggage carousel.
"Excuse me," he says quietly.
"You have a clump of rice stuck to your face.
"It's been there since dinner."
Vanuatu I love you, but I need some sleep.
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