'It might be a mistake.'

She nodded.

'Have you ever been in a serious relationship?' he asked.

'Once,' she said, 'a long time ago.'

'What happened?'

'He finished with me, and I was a snivelling wreck.'

'And then?'

She rested her chin on her hands. Sitting there in the moonlight, brow furrowed, she was utterly beautiful, but Johanson didn't feel a hint of regret about the way things had worked out. 'I was always the one who ended it,' she said.

'An avenging angel, then.'

'Don't be ridiculous. Mostly they got on my nerves – too slow, too sweet, too stupid. Sometimes I ran away to make sure I escaped before I. . .'

'So you're afraid of building a house in case a storm destroys it.'

'Maybe.' She frowned. 'But there's another way of looking at it. You build the house, then knock it down before anyone else can.'

Somewhere a cricket was chirping and another answered from the other side of the lake.

'Well, you almost succeeded,' said Johanson. 'If we'd slept together, you could have dumped him. Did you really think you could fool yourself like that?'

'I told myself I'd be better off having an affair with you than throwing myself into a relationship that might stifle me. Sleeping with you would have confirmed it.'

'So, you'd have screwed your way to safety?'

'No.' She glared at him. 'I was attracted to you, believe it or not. You weren't just there to help me escape. I didn't just-'

'It's OK.' Johanson made a dismissive gesture. 'You're in love.'

'Yes,' she said sullenly.

'Don't sound so grudging. Say it again.'

'Yes!'

'That's better.' He grinned. 'And now that we've turned you inside out and upside-down, let's drink to Kare.'

She gave him a lopsided grin.

'Still not sure?'

'Yes and no.'

Johanson passed the bottle from one hand to the other. 'I tore a house down once, a long time ago. The people were still inside. They both got hurt, but eventually it passed – for one of them, at least. I still haven't decided whether it was right.'

'Who was the other?' asked Lund.

'My wife.'

'You were married?'

'Yes.'

'You never said.'

'We're divorced.'

'Why?'

'That's just it. There was no real reason. No major dramas, no crockery throwing. Just the feeling that things were closing in. I was scared… of becoming dependent. I could see us starting a family. Soon there'd be children in the house and a dog in the yard, and I'd have to take responsibility.

'And now?'

'There are times when I see it as the only real mistake I've made.' He stared into the water. Eventually he straightened and raised the bottle. 'Now for a toast! Whatever you want to do, go ahead and do it.'

'But I still don't know,' she whispered.

TO JOHANSON'S ASTONISHMENT they spent the whole weekend together by the lake. After their failed attempt at romance, he'd imagined she'd want to leave first thing in the morning, but in fact the air had cleared. Their flirtation was over. So, they went for walks, talked, laughed and forgot about the outside world with its universities, oil rigs and worms – and Johanson cooked the best Bolognese of his life.

On Sunday evening they drove home. Johanson dropped Lund at her place, then went on to his own. As he stepped into his house in Kirkegata Street, he was struck by the difference between solitude and loneliness, but the feeling soon passed. He left it in the hallway: anxieties and melancholy were allowed that far but no further.

He took his case into the bedroom and turned on the TV. Zapping through the channels, he came across a concert from the Royal Albert Hall. Arias from La Traviata, sung by Kiri Te Kanawa. He started to unpack, humming with the music and wondering what he might like as a nightcap.

The music stopped, but he was folding a shirt and didn't register that the concert had ended. In the background, the news took over.

'. . . in Chile. It is not yet known whether the disappearance of the Norwegian family can be linked to similar incidents that are said to have occurred around the same time off the coasts of Peru and Argentina. In all three countries fishing-boats have disappeared or been found abandoned at sea. None of those involved have been traced. The conditions were calm and sunny when the family of five boarded the trawler on a deep-sea fishing expedition.'

He smoothed a sleeve and folded it to the middle.

'Costa Rica is currently experiencing a jellyfish invasion of unprecedented proportions. The so-called Portuguese man-of-war, or "bluebottle," has descended on the area, swamping coastal waters. Local media reports say that fourteen people have been killed by the highly poisonous creatures, while many others have been injured, including two British citizens and a German. The number of missing is still to be confirmed. The Costa Rican Foreign Office has called an emergency session of Parliament, but firmly rejects the suggestion that beaches should be closed, insisting that there is no real threat to swimmers.'

Johanson stopped what he was doing. 'Those assholes,' he muttered. 'Fourteen dead! They should have closed the beaches long ago.'

'Swarms of jellyfish are also causing concern off the coast of Australia. This time the culprits are thought to be box jellyfish, another highly venomous species. The local authorities are urging people to stay out of the water. Over the past hundred years, box jellyfish have caused seventy deaths, making them more dangerous to man than sharks.'

'In another story of marine tragedy, fatalities have been reported off the coast of western Canada. The exact cause of the accidents, which resulted in the sinking of several tourist vessels, is not yet known. Reports suggest that navigational errors may have caused them to collide.'

Johanson was gazing at the screen now. The newsreader had put down a piece of paper and was smiling emptily into the camera. 'And now for a round-up of today's other stories…'

Johanson thought of the woman he'd seen in Bali, who'd flailed in the sand, shaken by convulsions. He hadn't touched the creature and neither had she. She'd been walking along the beach when she noticed something floating in the shallows and had fished it out with a stick. Cautious by nature, she'd kept it at arm's length, turning it this way and that. Then she'd made a mistake.

The Portuguese man-of-war belonged to the genus Physalia, a type of hydrozoa that scientists still found baffling. Strictly speaking, it wasn't a jellyfish but a floating colony of tiny organisms, hundreds of thousands of polyps, grouped according to function. The main body, a jelly-like float tinted violet or blue, had a gas-filled crest that rose above the water, allowing the colony to sail across the surface. You couldn't see what hung beneath it.

But you knew as soon as it touched you.

A net of tentacles up to fifty metres long and covered with miniscule stinging cells swept beneath each Portuguese man-of-war. The structure and purpose of the cells was a masterstroke of evolution. Each consisted of a hollow sphere that curled in on itself to form a coiled tube tipped with a harpoon-like barb. At the slightest touch the tube would unfurl, bursting forth at a pressure equivalent to seventy exploding tyres. Thousands of barbed harpoons would penetrate the victim's flesh, injecting a mixture of phenols and proteins that attacked the blood and nerve cells. The victim's muscles would contract and pain would sear the skin. Shock would follow, then breathing difficulties and heart failure. Those fortunate enough to be close to the shore usually survived, but divers and swimmers further out stood little chance against the trailing tentacles.

The woman on the beach in Bali had dropped the hydrozoan but the stick had brushed her toe. It must have left a trace of venom – enough to ensure that she never forgot it.