It was my first time. I'd never sailed before. The rich parents of a school friend judged me suitable company for their troublesome daughter - more suitable than the young man they were dragging her away from, at least. I was invited along to keep her entertained. Her name was Penny and she considered this wonderful holiday a brutal kidnapping, by the man and woman she called RF (rotten father) and WSM (wicked stepmother).

The vessel, an old fashioned sailing ship with three masts and more crew than passengers, was idling from island to island in the waters north of Irian Jaya. This particular evening the peach-rose sunset backlit an exquisite little jewel of an island with beaches of such loveliness the captain decided we should stop for the night.

By the time the last streaks of deep crimson had faded, most of the passengers were out on deck: playing cards, sipping cocktails, or leaning on the rails, admiring the pretty moonlit beach, listening to the lapping waves.

As the moon rose higher, I spotted a figure standing still as a statue on the sand. I pointed it out to Penny but, at that moment, the SM (I dropped the undeserved 'W') hailed the RF who was involved in a card game, a few feet away. She wanted him to come and look over the side of the boat.

Curious, we looked down too.

'Ooh', I squealed, 'the water's glowing!'

The RF left his game, strolled over and looked over the rail. He smiled.

'It's bioluminescence', he said. 'Can you see all the little creature - thousands of them - swimming close to the surface? They glow in the dark. It's quite a spectacle, isn't it?'

'Humph', Penny shrugged, looking unimpressed. 'We've seen it all before. My father and his wife have had dozens of sailing holidays. I wonder they even notice these trifles any more.'

She was still sulking about the kidnapping. It wouldn't matter how often I saw the ocean lit from beneath by shimmering creatures rising from the deep - it's a magical sight. I'll never tire of it.

The moment of wonder was interrupted by an ululating bellow from the shore. We looked up. It came again, drawing our eyes towards the figure standing there, unmoving. We could see him clearly now, lit from above by the moon and from below by the green, phosphorescent glow rippling in the foam lapping his feet. He looked ghastly. He didn't move - didn't wave or wade into the water. Nor did he step back to avoid wetting his feet. By this time, just about everyone on deck had drifted to the port rail to gawk and speculate. The captain barked a warning that we were unbalancing his craft, so we hastily moved back.

The SM plucked a pair of opera glasses from her bag and raised them. After staring for a few moments she drew in a sharp breath, dropped the glasses and caught the RF's arm. He somehow managed to catch them before they could hit the deck, without withdrawing support from his wilting wife. Then he looked through them himself. When he lowered them, his expression was troubled. He put a protective arm around the SM, and guided her to a seat.

In the meantime, our torrent of questions were stifled when further yells rang out from the shore. Inexplicably, the sounds seemed not to be coming from the figure on the beach, who continued to stand as though in a trance. The babble from fellow passengers sank to a whisper when a life-boat was launched and a couple of crew members rowed beachward.

We watched as the rowers beached, jumped out and approached the figure. They spoke to him. They turned and pointed to the ship. Still he didn't move. Tension must have been building. I wasn't even aware that I was gripping the rail and holding my breath until Penny nudged me and almost jolted me out of my skin.

'What do you suppose is up with the RF and the WSM?' she wondered.

I shrugged. 'How should I know? They're your parents...'

'Only one of them... '

'Shush. Look,' I interrupted, impatient with Penny's endless sulking, when more interesting things were afoot.

The sailors were picking him up bodily. He didn't make the least objection, as they carried him to the little boat. He was as stiff as a corpse in a state of rigor mortis.

It looked as though they were rowing across an enchanted lake: the glow darkening and brightening in concentric circles as the oars dipped, and the bow-waves throwing out glittering, green-gold spray.

He had to be hauled up to the deck by a rope tied around his chest. As the sailors eased him over the rail, there was a commotion back at the beach.

A crowd was pouring onto the sand from beneath the trees. Sounds of drumming and chanting filled the night. As we watched, arm-fulls of wood were piled up and lit and the people began to dance around the fire. This scene could have been recognised and understood by people the world over. The islanders were celebrating.

Some of the passengers wanted to go ashore and join in the fun, but the captain wouldn't have it. The natives might not be friendly, he said. They were reputed to have a taste for missionaries in these parts. I assumed he was joking - but he went on to say that more than one 'man of the cloth' had been deposited hereabouts, and never seen again.

Disappointed, they returned their attention to the new arrival - who continued stiff and uncommunicative. He made no response to the captain's questions. Someone brought him a chair, but it was as though he couldn't hear or see the people around him. What a strange, grotesque looking individual he was: filthy and unkempt, wearing the tatters of what appeared to be an ancient black suit. His jaw clenched and unclenched as though working on something unpalatable, and his eyes slowly started to kindle with rage, but seemed focused elsewhere - on a dreadful scene, that he alone, could see.

He was clearly quite mad but, as disturbing as he looked, I couldn't see why the SM had reacted with such horror when she saw him through her glasses.

Penny pulled me into the shadows of the cabins and told me to pipe down when I complained. Her parents were talking quietly and she wanted to sneak up and eavesdrop. Curiosity was gnawing at both of us. True, the stranger was no oil painting, but nobody else in the company was fainting at the sight of him. We were beginning to get the impression that Penny's parents knew the identity of the dishevelled lunatic.

We crept close enough to listen. The RF was protesting, that he had been assured, categorically, that the natives of this island had 'swallowed' every missionary that had ever set foot here.

'The way your overbearing husband bullied and harangued you and the crew - it was obvious he'd give his new flock hell. I didn't think a tribe of cannibals would tolerate his fire and brimstone threats and promises for any longer than it took them to fill a pot with water and herbs.'

'I know,' she sniffed. 'They must have given up cannibalism. Or maybe your information was just wrong. We didn't even recognise the island, did we? Maybe the cannibals are on a different island.'

'What rotten luck,' he muttered. 'Doubly rotten that they should've modified their diet so inconveniently and that we should have chanced back to this very island. Out of all the hundreds of islands, why this one?'

Drying her eyes, she said 'Those poor people. No wonder they're celebrating. How they must have longed to be rid of him.'

Their whispering ceased when the mad man - now able to place one foot in front of the other - was escorted along the deck. His eyes were no longer fixed on that awful otherworld, but were roving over the people around him. He spotted Penny's parents and stopped, fixing them with a baleful stare. Then he raised his hand, pointed at them and roared:

'YOU! Godless heathens! You diverted my mission for your own purposes. You must have known!'

He paused for a moment, looking suddenly confused.

They blew dust in my face. Dust!

Then almost screaming:

'Devils! Whenever I came out of the waking nightmare, and began to remonstrate, they did it again!'

They dragged him away, raving that he'd seen hell and swearing that it was too good for those godless heathens.

Penny's parents just gaped.

They obviously didn't know about the orchids. Neither did I, until years later. They grow on some of the islands of Indonesia. Whilst carefully avoiding the seeds themselves, natives grind them into dust that induces a zombie-like trance in nuisance neighbours - and other enemies.