ichael threw the last piece of pizza crust into the box, then methodically put the remains of his meal in a black plastic bin liner. He'd given Kevin the rest of the day off, because if he had to spend another hour listening to his mindless attempts to pick a winning horse, he'd have had to take steps to silence his sidekick permanently. Besides, there was nothing doing.

The big fucker had left in a taxi with a holdall three days ago and hadn't been seen since. He hadn't been suited up like a man going on a business trip. But what did Michael know about the way second-hand car dealers did business? Maybe they met regularly for conventions in jeans and sweatshirts and waterproof jackets. Maybe Gourlay was going off for a few days' fishing with his mates. The stress of living with a woman climbing the walls about her missing kid would drive any man to the quiet of a trout stream.

Since he'd gone, Bernie had barely left the house, other than to visit the supermarket to stock up on ready meals, whisky and fags. Patrick had sounded bored with the whole business when Michael had called in, but he wasn't for putting a stop to it. When Michael had asked if he wanted to continue, Patrick's voice had turned to steel and he'd said, "It's over when I say it's over, and not before. You'll be well looked after, Michael. I know it's not very interesting, but, when the time's right, there'll be plenty for you to do."

So he'd settled in for the evening, his miniature radio tuned to a jazz station, the lights off and the binoculars sitting on their tripod in front of him. OK, it wasn't the most exciting job in the world. But Michael had seen more than his fair share of excitement over the years. He understood very well that there was a lot to be said for the dull. He shifted his position, getting comfortable in the camping chair he'd bought when they'd got their hands on the flat. Another night, another dollar.

Lindsay and Rory drained their teacups and exchanged a slightly apprehensive look. "What's to be scared about?" Lindsay said, going for bravado.

"Right. I mean, I went to Lesbos and lived. How bad can it be?"

They grinned in complicity and emerged into the corridor. Dimitri appeared, looking disturbingly cheerful. "You are ready?" he demanded.

"Ready for what, exactly?" Lindsay asked.

"The beating, the beating," he cried, enthusiastically waving his arms.

"You didn't tell me this was the S&M banya," Rory muttered.

"It was your idea."

"Maybe, but you're still going first."

They followed Dimitri back into the wooden cubicle, but he shooed Rory back out again. "Wait in sauna," he said. To Lindsay, he added, "Lie face down on bench. Take sheet off."

Then he disappeared. When he came back, he was wearing nothing but a towel round his waist and a felt hat that looked like a left-over prop from Bill and Ben the Flowerpot Men. He was also bearing two bunches of birch twigs. Oh shit, Lindsay thought. I'm naked in a steam room with a nutter.

First, Dimitri got the room hot and humid, then he started gently wafting the birch twigs over her body. This created an updraft, bathing Lindsay in moist air while simultaneously what felt like hot rain was pattering over her back. Then the birch twigs descended and the length of her body was covered in a blend of gentle switching and firmer strokes. Just when she was getting used to this and thinking it was really rather pleasant, the hot bundles of leaves were clamped without warning on her large muscles like a fluffy hot mustard poultice - shoulders, lower back, buttocks, thighs, calves and finally feet. Her skin was tingling with damp fire.

Then Dimitri yelled, "Cold shower, now, cold shower," and sent her scuttling off to shout out loud as she froze in the icy jets. By the time she emerged, she could tell from the exclamations that Rory was undergoing the same sweet torture. Lindsay went into the sauna, where the dry heat felt strange after the banya. She mused on what Rory had revealed earlier, thinking it sounded a little too pat as an explanation for her friend's violent allergy to committed relationships. Lindsay wondered if the real reason for Rory's avoidance of love was more to do with her mother's death. Losing the one person she'd loved and trusted in such a traumatic and treacherous way would leave anyone wary of a repeat experience, she thought sympathetically. She'd endured betrayal herself and understood only too well the scars it left behind. It would take Rory a long time to recover from something so profound.

Rory eventually joined her in the sauna. "They should have these in clubs instead of chilling-out spaces," she groaned comfortably. "I can't remember the last time I felt so completely laid back."

"Better than sex," Lindsay said.

"You've obviously been doing it wrong."

Lindsay giggled. "The thing with sex is you have to expend a lot of effort to feel this good. But here, somebody else does all the work." She stretched out on the top bench, enjoying the sensation of the muscles round her spine relaxing.

A few minutes later, Dimitri banged on the door. "Your time is over, ladies," he called.

As if in a trance, Lindsay and Rory made their way back to the changing room and got dressed. "Do you know, I haven't thought about Jack Gourlay since before we had our tea," Lindsay said dreamily.

Rory gave a slow smile. "Who's Jack Gourlay?"

The skies were grey over the Gulf of Finland, a Force 5 wind blowing out of the north-west. Tam Gourlay inched his way from the galley to the hatch leading to the cockpit, cradling a mug of tea in his hands. Boats like this weren't designed for men of his size, he thought as he forgot yet again to duck under the bulkhead and caught the side of his head a glancing blow. He leaned forward and held the drink aloft. Andy Gordon bent at the knees and took one hand off the wheel to take the tea, his sharp blue eyes never leaving the gunmetal swell ahead of the full belly of the genoa sail. "Cheers," he said.

Tam clambered up the short companionway and joined Andy in the shelter of the sprayhood. "How are we doing?" he asked.

"No' bad. It makes a change, having to watch the charts all the way through the archipelago. I'm used to water I know better than the back of my hand."

"Must be a bit different, sailing a wee thing like this instead of driving a big fishing boat," Tam said.

"Aye. It's like riding a bike, though. You never lose the knack." He leaned into the wheel, his shoulders bracing against the swell. It was hard to see a resemblance between Andy Gordon and his daughter. The balding man with the broad back and the short legs was a completely different physical type, and his blunt, ruddy features gave far less away than Lindsay's open countenance. Only in the eyes was there any congruence. The same spirit that lit Lindsay from within was there in Andy Gordon's blue gaze as he scanned the horizon.

Tam sat down on the damp plastic cushion that ran along the side of the cockpit, grateful for the oilskin trousers Andy had supplied him with, even if they were six inches short in the leg. He watched the fisherman standing rock-steady on the shifting deck, marvelling at such stamina from a man in his sixties. They'd hardly stopped since they'd left Glasgow. When they'd reached Helsinki, they'd had to go straight to the Russian embassy and queue for a couple of hours to get their three-day visas. Then they'd gone to the boatyard to pick up the yacht they'd chartered from Glasgow, which Andy insisted on checking from stem to stern before he'd accept it. Andy had stayed at the wheel through most of the previous night, only dropping anchor in a sheltered cove an hour before dawn and snatching a couple of hours before they'd set off again. Tam hadn't expected to sleep, with the combination of the unfamiliar motion and his anxiety about what lay ahead, but he'd surprised himself by going spark out for over six hours. "Will you get a proper sleep tonight?" Tam asked.

Andy nodded. "We should be in clear water before too long. Then I can set the autopilot and get a few hours."

"You'll be on your knees at this rate."

"Ach, it's only a couple of nights. I can catch up when we get to port tomorrow night. And I'll have Lindsay to help me on the way back. We can split the night watch between us."

Tam shook his head in admiration. "I can hardly believe the way she's set this whole thing up. She's some lassie."

Andy's mouth twitched at the corners. "She's that, all right. Christ knows where she gets it from. Me and her mother, we've no' got an adventurous bone in our bodies. We were born in Invercross, and we'll probably die there. But ever since she was wee, Lindsay's aye been one for diving in at the deep end. And this time, I couldnae stand back and leave her to it. Not when I could do something a bit more useful than just giving her Sasha's phone number." He leaned across and checked the chart, scanning the horizon for the next landmark. "A wee touch to starboard, I think."

"I really appreciate you doing this," Tam said. "Lindsay told me you insisted, wouldnae take no for an answer. That means a lot, you know. The way you've weighed in when it's no' even your fight."

"You dinnae have to keep saying that, son. I know fine. We'll get it sorted, don't you worry. My pal Sasha, he'll see to that." He screwed his eyes up against a stray drift of spray. "Tell you the truth, I cannae quite believe I'm here myself. That lassie of mine has a way of making the world dance to her tune."

Right then, Andy Gordon's lassie was sitting in the Georgian restaurant Sasha had recommended, contemplating a dish translated on the English menu as "meat drunk on the plate". Rory, who was tucking into a grilled salmon fillet, had taken one look at the steak smothered in diced vegetables with a cream sauce and said, "I can see how it got its name. It looks like somebody threw up over a piece of beef."

"Thanks," Lindsay said, cutting into her meat. "That'll do wonders for my appetite. But you've got to live dangerously sometimes."

Rory glanced up from under her eyebrows. "Just so long as I don't have to eat things with names like that."

There was silence while they ate their food, washed down with a chewy Georgian red wine. "It's probably better if we split up tomorrow, cover our options. Sasha can take one school while we go over to the one where Jack's most likely to be enrolled. I've checked on the map and it's quite near a metro station on the same line as the one up the street. Getting there should be pretty straightforward," Lindsay said.

"Famous last words. What are we going to do if we find it?"

"Wait and see if Jack arrives. And if he does, follow the person who brings him to school back home. That should tell us where he's staying."

"And then?" Rory pressed on relentlessly.

"I don't know. We'll have to see how it goes."

"And what if he turns up at the one Sasha's watching?"

"He'll do the same thing," Lindsay said. "Then he'll come back and pick us up. And then we'll make our plans."

"Doesn't it scare you?" Rory asked, her eyes fixed on Lindsay's. "Knowing we're about to embark on a criminal act in a country that's not noted for the even-handedness of its judicial system? Not to mention the prevalence of guns?"

"Of course it scares me. That's why I'm trying very hard not to think about the possibility of getting caught. I'm visualizing the scene when Jack's reunited with his mother and I'm standing there taking the photos. It takes my mind off the alternative." It was the truth, but not the whole truth. There were other things on Lindsay's mind that had nothing to do with the fate of one small boy. But she knew she really shouldn't be thinking about them either.

"Good trick if you can manage it. But it's definitely winding me up. Shall we get another relaxing bottle of wine?"

Lindsay's expression turned quizzical. "Is the effect of the banya wearing off already?"

Rory laughed. "Listen, you don't want to go there. That banya has had some very strange side effects, let me tell you."

"Like what?" Lindsay felt the thin ice creaking beneath her words. She didn't think she was imagining the sparkle of electricity between them.

Rory held her gaze for a moment, then looked away, shaking her head. "Nothing I want to discuss in a public place." Her words were almost drowned by a noisy burst of laughter from a neighbouring table.

"Look, why don't we get the bill? We can buy a bottle of wine in the hotel bar and drink it in peace," Lindsay suggested. Rory nodded agreement.

As they strolled down the street towards the hotel, the warm evening air balmy against their faces, Lindsay was feverishly conscious of Rory's body inches from hers. It was as if she was radiating heat like the brazier in the banya. This is crazy, she thought. Eight years you've been with Sophie and never once crossed the line. You're working with this woman, for God's sake. You're maybe going to be a parent. Aren't you taking enough risks already without going overboard? Put the lid on it now. But her interior monologue had no effect on the churning in her stomach or the prickle of sweat along her spine.

They walked into the hotel and Lindsay turned towards the bar. "Another bottle of red?"

"Maybe not," Rory said. "Maybe I don't need it after all."

They didn't speak in the lift, but it was a silence that crackled with what wasn't being said. Lindsay fumbled with the key, struggling to get it into the lock. Then she managed it and they were inside the suite. "I thought I'd sleep in here on the divan, let you have the double bed," Lindsay gabbled as she flicked the switch to turn on the table lamps. She turned to watch Rory's reaction but couldn't see her eyes through the shadows.

One side of Rory's mouth rose in a knowing half-smile. "You know, I've seen you stripped to the skin tonight. But you look a hell of a lot sexier with your clothes on."

Lindsay cleared her throat. Her voice came out half an octave higher than usual. "Delirium. That would be one of the strange side effects of the banya, right?"

The moment broken, Rory walked away and feigned an interest in the St Petersburg tourist magazine on the writing table. "Right enough," she said, her tone darker and colder. "Should you maybe phone home?"

Lindsay took a couple of steps towards Rory. "I don't want to phone Sophie."

"She'll be worried about you. Running around Russia like James Bond." There was no mistaking the coolness now.

"No, she won't. I called her on my mobile when the receptionist was booking the banya. Just to let her know we'd arrived safely."

Rory turned her head, the half-smile back in place. "She really shouldn't be worried about you, should she?" This time, the tone was regretful.

"Why are we talking about Sophie?"

"Because it puts a wall between us, Lindsay. And that's the sensible option."

Lindsay ran a hand through her hair. "I'm not good at sensible."

"Neither am I. So let's work on treating this as a 'sensible' workshop for both of us." Rory swung round to face Lindsay and leaned against the writing table. The subtle light of the lamps cast the planes of her face into relief. Lindsay thought she had never wanted so badly to kiss someone.

"You think that'll work, do you? You think we can just ignore whatever it is that's happening here?" There was no aggression in Lindsay's questions, only a simple plea for answers.

Rory spread her hands. "What's the alternative? I want us to be able to work together. I like working with you. I don't want to fuck that up."

"Me neither. But we can't pretend we're indifferent to each other. It's not going to go away."

"If we don't feed the flame, it'll die," Rory said.

Lindsay shook her head in frustration. "You know that's bullshit. We'll always be wondering what it would have been like. It'll be sitting there between us in the Caf¨¦ Virginia every bloody day. So let's get it out of our system."

Rory laughed out loud. "You know, that's probably the least seductive thing anybody's ever said to me. 'Come on, let's get it over with. One shag with you and I'll be cured,' " she spluttered.

The laughter was infectious. Lindsay couldn't help herself. All at once she was chuckling too. Somewhere in the middle of the laughter, they fell into each other's arms. Two hungry mouths connected.

Suddenly, sensible was history.