It's a moonless night, and high above our heads a blade of red fire glows in the black sky. It's just possible to make out the silhouette of the cone as the volcano flares and dies, like a living, pulsing beast. A tongue of molten lava dribbles down its flanks until it disappears, swallowed in the dark of the sea.
We're travelling along the north coast of Papua New Guinea on day three of our expeditionary voyage aboard the MV Orion.
This is like no other place on Earth. Wild, mysterious, raw and tantalising, it is a perfect fit for the traveller in search of adventure. The PNG terrain is formidable - a spine of unbreachable mountains guttered by vast rivers and impenetrable swamps. It also has the richest ethnography of anywhere of comparable size - about 800 language groups - and a mosaic of tribal cultures that includes some of the most flamboyant people on the planet.
The severe nature of PNG's topography keeps the wider world at bay, but its seas and rivers provide an entree to this amazing world. We're on an 11-night cruise between Rabaul and Cairns, exploring the villages and islands along the country's north coast, east as far as the Trobriands and into Milne Bay, at the forked tail of the bird-shaped island.
Apart from two days at sea, we're onshore most of the time. By night we sail, and every morning wake to another village of thatch and sticks set on a palm-lined shoreline with outrigger canoes bobbing around our stern. At Watam Village, we're met by warriors who dance beneath a dragon that looks uncannily like one from Chinese New Year, weaving to the sound of hand drums and chants.
At Tufi, we board a speedboat from the local dive resort to travel deep inside one of the fiords, formed by a coastal volcano and etched by wind and waves into steep-sided sea canyons furred with greenery.
Deep in the armpit of the fiord, we transfer to outrigger canoes paddled by lithe boys and girls decorated with flowers and ferns. We paddle for about a kilometre along a narrowing ria through a green tunnel of nipa and pandanus palms. Suddenly, a call erupts from the bush, and a black figure bounds from somewhere behind us carrying a spear as he charges through the knee-deep water, screaming. An act, luckily, all choreographed, but some hearts take a flutter.
At every stop it's a warm welcome, and whether it's on the concrete quay in Madang, or a coral beach in the Tami Islands, there's a sing-sing. Throughout PNG, body decoration is raised to an art form. Using feathers, palm leaves, berries and shells, villagers create elaborate headdresses and costumes, decorate faces and bodies with paint and oil and perform sing-sings, the dance-drama that is universal here.
Most memorable of all is the sing-sing on our day in the Trobriands. This is the South Seas paradise - a grass-skirt, thatch-roof, hibiscus-hung tropical heaven. Almost a century ago, the anthropologist Bronislaw Malinowski set the tone for the Trobriands when he published a book on the islanders' social customs, with the potboiler title The Sexual Life of Savages. The Trobriands have been saddled with the subtitle "The Islands of Love" ever since. Although this has led to many misconceptions about Trobriand Islands life, the local sing-sing is a hot-blooded affair, a nubile, hip-swinging romp through the palm trees performed by adolescents with glossy black bodies polished with charcoal and coconut oil.
Each village offers a retail experience. The people of PNG are expert carvers and craftsmen whose masks, drums, pottery and necklaces are powerful, haunting creations inspired by a rich culture of legends and dreams.
Shopping has a slightly haphazard character. One seller might ask 200 kina ($115) for a carved canoe prow decorated with cowrie shells, while his neighbour might ask 60 kina for a near-identical piece. "How much for this?" I ask an elderly man on the island of Kitava, picking up a hardwood carving of an octopus inlaid with mother-of-pearl.
"Fifty kina," he says. "Or maybe 20." I buy it for 30, and leave to the sound of his wife and daughter giving him a hiding.
Our last stop is Alotau in Milne Bay, a regional capital with paved roads and supermarkets, where several of us head off in search of bags and even suitcases to transport the excess loot we've bought along the way.
Around the islands we are sailing through, the peacock colours below the surface suggest a treasury of corals and marine life. Several times during the voyage we don face masks, snorkels and fins and loiter while clownfish, parrotfish, angelfish and wrasses dart below.
There's revelation here, too: PNG comes undiluted from the pages of National Geographic, yet where are the visitors? And where are the Australians, the New Zealanders? The irony is that over dinner tables in Milan or New York, this is spoken of as a glamour travel experience. Yet here, mention PNG as your next holiday destination and the alarm bells ring.
True, the streets of Port Moresby are no place to wander after dark, and the Highlands Highway is notorious for its raskol gangs, but PNG is not so much dangerous as different.
In the villages we find nothing but charm, warmth and smiles. Retired mining engineers and money managers return to the ship wearing floral garlands. Women are frequently escorted through the villages by small children who clutch their hands.
As an expeditionary cruise vessel that carries a maximum of just more than 100 passengers, the MV Orion is lavishly endowed and just as capable of operating among penguins and leopard seals in Antarctica as it is with flying fish in the Coral Sea. There's a spa, beauty therapist, boutique, lecture theatre, two inside restaurants and one on deck, two bars, a gym and a library. Early-morning yoga classes are held outside on the sundeck. Every afternoon at 4.30 is team trivia time, accompanied by a scrumptious afternoon tea.
Cabins come in three styles, ascending in size and magnificence as they rise from deck three to five, but even the most modest are large and luxurious, with en suite bathrooms, satellite internet hook-ups, oodles of storage space, glossy wood veneer and nautical brasswork.
Meals offer endless opportunities for waistline expansion. Breakfast and lunch are buffets with fresh croissants, fruit salads, eggs benedict and smoked salmon on the menu. There are fish salads and sliced meats, icecream made on board and a decent cheese platter for lunch, a proper afternoon tea, and espresso any time I feel like one.
Apart from the barbecue nights, dinners are a five-course table d'hote menu by Serge Dansereau of Sydney's acclaimed Bathers' Pavilion. Fish is prominent, and several times during the voyage the chef goes ashore to buy from the locals.
It's a cruise for connoisseurs of the unusual who want to travel with maximum creature comforts. When we leave the vessel for the Zodiacs, there are beach towels spread out to protect tender flesh from hot rubber. Solicitous arms help us to board, and hold the boat on the beach against the slosh of the sea. There is always a waiter nearby who knows how you like your coffee and is ready with a cool towel when we return to the ship.
The Orion also carries an expedition team who together make up a compendium of scientific, ethnographic and technical expertise. Sue Flood is a noted wildlife photographer who specialises in polar regions and whose images have appeared in National Geographic. For many years she worked with David Attenborough at the BBC's natural history unit.
Her photo tips and slide presentations inspire even the point-and-hope snap shooters among us to greater heights. Chris Cutler is a naturalist and field biologist who spent several months in a Sepik River village being devoured by mosquitoes while he hunted butterflies. Orchestrating our shore excursions is Justin Friend. Erudite and experienced in the manners and mores of PNG tribal life, he illuminates our travels with his insider knowledge of everything, from the intricacies of New Guinea pidgin, the no-frills lingua franca, to the wearing of penis gourds.
One evening, before dinner, Friend gives a hilarious account of a highland wedding - his own - which involved the building of a house, the buying of pigs for the bride price, a feast for hundreds that turned into a riot, and a murderous father-in-law with an axe to grind, preferably in Friend's cranium.
The voyage aboard the Orion through PNG is not for everyone. The country's cultural and scenic splendours do not come cheap, nor does it fit conveniently into travel agents' schemes. Yet, if you want to wake up daily in a world where magic and mystery still holds sway, there's nothing quite like it.