Tamsin Rooke had a gift for denial, and she had never needed it more than she did the morning after the chart wrote their names.

She came up on deck at five with her braid freshly bound, her boots laced to the ankle, and her face arranged in the expression of a woman who had slept like a log. She greeted Odo with a brisk nod. She gave Juno a thermos of tea and an unnecessary lecture on the correct way to coil a mooring line. She checked the engine log, the fuel gauge, and the weather glass, in that order, and wrote her initials on each with a firm, steady hand.

She was a professional. She had a boat, a crew, and the biggest Open Tide of the season waiting at the end of the breakwater. She did not have time for what had happened last night.

It had not happened.

She repeated this to herself with the fixed intensity of a sailor reciting a catechism in a gale. It was a trick of the lamp. It was a piece of old parchment doing what old parchment did. It was a very long day, a very short night, and a woman with a bad habit of reading too much into the movement of ink. She had been tired. She had been upset. She had said some foolish things to a roll of paper in the dark, and that was the end of it.

"Morning, Captain," said Ila.

She was standing at the foot of the wheelhouse stairs in her sage-green waterproof, with her hair tied back and her hands in her pockets. She looked pale. She looked as though she had not slept either. But there was something steady in her face, something quiet and clear, and she met Tamsin's eyes without flinching.

"Pilot," said Tamsin.

"Is the weather glass reading steady?"

"Steady."

"The surge numbers?"

"Within tolerance."

"Good." A pause. "Is there anything you want to discuss, before we cast off?"

"No."

"Nothing at all?"

"Nothing at all," said Tamsin, and was proud of how even it sounded.

Ila looked at her for a moment longer. Then she nodded, once, with a faint curve of the lips that was not quite a smile, and climbed the stairs.

Tamsin watched her go. She noticed that her own hands had gone tight on the rail. She loosened them, one finger at a time, and went to check the lines.

* * * The great Open Tide ran perfectly.

It was almost insulting. For eight hours the Marrow Lark moved through the Drift like a hot knife through butter, and every one of her crew performed with a bright, grim, hyperefficient courtesy that would have done credit to a naval drill. They hauled a stranded trawler off the north side of Bell Rock. They towed two fishing dinghies out of a kelp trap. They rescued a family of five from a sinking island of drift ice that had no business being there in summer. Ila ran the numbers with bell-like clarity. Tamsin ran the deck. They spoke only in the clipped monosyllables of the trade.

"Port ten."

"Port ten, aye."

"Hold her there."

"Holding."

"Thank you."

"You're welcome."

It was the most polite eight hours of Tamsin's life. By the time they limped back to berth nineteen at four in the afternoon, soaked, salt-crusted, and utterly exhausted, she had said the word thank you eleven times, and each had felt like swallowing a stone.

"You two," said Juno, on the dock, in a hushed and awed whisper, "are being really weird."

"We're not."

"You are. You've been like this all day. It's like watching two robots do a tea ceremony."

"Juno."

"You said 'please' to the winch. I heard you."

"The winch is a delicate instrument."

"You called Ila 'Pilot Sorrel.' To her face. In the middle of a rescue."

"It's her title."

"You never use titles." He folded his arms. His face was earnest and exasperated and slightly pink. "Captain, are you fighting? Is it me? Did I do something? Because if it's about the tea, I know I put too much sugar in last time, but I didn't think."

"We're not fighting," said Tamsin.

"We're not fighting," said Ila.

They had spoken at the same instant, in the same tone, with the same slight lift of the chin.

They both stopped.

Juno looked from one to the other. His eyebrows climbed slowly, in a manner that suggested a man witnessing a very small natural disaster.

"Oh," he said. "Oh, wow."

"Don't," said Tamsin.

"You said it at the same time."

"It was a coincidence."

"It was exactly the same pitch."

"Juno," said Ila, with a note of quiet desperation, "I think there's a coil of line that wants seeing to."

"There's always a coil of line," said Juno, but he retreated, backward, grinning, with his hands raised in surrender. "I'm going. I'm going. I'm just saying that if there was an Olympic event for pretending nothing's wrong, you'd both be on the podium."

He vanished into the wheelhouse.

Silence fell. It was very awkward. The wind rattled the rigging. Somewhere on the dock a radio played a thin tinny waltz.

"I'm sorry about that," Ila said at last.

"It's nothing."

"He's very young."

"He's very observant. It's a dangerous quality in a deckhand." Tamsin picked up a coil of line and hung it on its hook. Her voice sounded stiff and wooden in her own ears. "We'll be more careful."

"More careful."

"I think it would be best."

"Yes," said Ila, after a moment. "Of course."

She did not say anything else. But as she turned away, Tamsin saw something flicker across her face, a small, tender, rueful look, like a person saying goodbye to a thing they had not quite had.

She went below and stood in her cabin for a long time with her palms flat against the door.

* * * The call from Corra came at six that evening.

It came on the ship's radio, a polite, crisp, unhurried voice crackling through the little speaker in the galley. Tamsin recognized it at once. She had heard it a thousand times in her life, in a thousand different tones, and she knew every register. This was the cool one. The one that meant business.

"Marrow Lark, Marrow Lark. This is Venn Ferries, Corra Venn speaking. Captain Rooke, if you have a moment."

She took it in the passage, with the door closed.

"Corra."

"Tam. I won't keep you." A faint hiss of static. "I wanted to say, congratulations on today. I heard about the trawler. Neatly done."

"Thank you."

"I mean it. Not many could have pulled her off Bell Rock at that angle."

"It was a team effort."

"I'm sure." Another pause. When Corra spoke again, her voice had changed. It was softer, lower, more careful, with the particular gentleness that Tamsin knew, from long experience, meant trouble. "I wondered if I might ask you something. Off the record."

"Go on."

"It's about the chart."

Tamsin went still.

"I've heard some talk," said Corra. "Around the harbor. Nothing definite. Only that there's been a light in your cabin. At night. A gold light. Bridget Pettibone's niece saw it from the dock last Tuesday, and again on Saturday, and she's told half of Saltwick that your porthole was glowing like a lantern."

"Bridget Pettibone's niece is fourteen and thinks the moon is a spaceship."

"I don't doubt it." The faint dryness crept back into her voice. "But I've known you a long time, Tam. And I've known that chart nearly as long. And I know that in all the years it's been in your family, it's never so much as twitched."

"What are you asking me?"

"Is it reacting?"

"No."

"Tam."

"I said no."

"You don't lie well. You never did." She sounded almost fond. "Is it reacting? Has it done anything? Drawn anything? Shown you anything at all?"

"Why?"

"Because if it has, there's something I need to tell you."

Tamsin's hand tightened on the receiver.

"Is she with you?" said Corra, very gently. "When it moves? Is Captain Sorrel nearby? Does it only wake when she's in the room?"

The passage seemed to tilt.

For a long moment Tamsin could not speak. The question hung in the air, quiet and sharp as a needle, and she felt the old cold knowledge settle round her heart like a hand. She thought of the cafe, and the whispered words, and the sudden terrible stillness on Ila's face. She thought of the white-fronted doors of Venn Ferries, and a figure in a green jacket coming down the steps with the look of a person who had just made a decision.

"How do you know that?" she said.

"I don't. I'm asking."

"You wouldn't ask unless you knew."

"I'm guessing, Tam. It's a good guess, but it is a guess."

"Who told you?"

"No one told me."

"Did she?"

"Did who?"

"You know who."

There was a short silence on the line.

"I think," said Corra, with great care, "that you should talk to your pilot."

The line clicked off.

* * * She found her on the stern deck, in the long gold light of evening.

Ila was alone. She stood at the rail with her elbows on the steel and a mug of tea cooling in her hands, looking out toward the harbor mouth, where the last of the fishing boats were coming in with their lamps already lit. The wind had dropped. The sea lay still and glassy. A scatter of gulls drifted in lazy circles above the mast, and the sunset lay flat and amber over everything, turning the water to hammered brass.

She looked peaceful. She looked, Tamsin thought, almost happy.

It made what she had to say a great deal harder.

"Did you tell Corra?"

Ila turned.

She had clearly been expecting something, but not this. A wave of confusion crossed her face, and then a slow dawning wariness, and her fingers tightened around the mug. She did not speak. She only stood, perfectly still, with her head tilted slightly to one side, like a deer in a clearing.

"I asked you a question," said Tamsin.

"I heard it."

"Did you tell her?"

"Tell her what?"

"About the chart. About what it does. About the light in my cabin." Her voice was shaking. She hated it. "She rang me tonight. She knew. She knew it only moves when you're close. She asked me directly, she asked whether it reacted to you. And I'd like to know how she got that idea."

"Tam."

"How?"

"I didn't tell her anything."

"You went to see her."

"I went to see her, yes."

"You went into her building. I saw you come out. You looked like you'd been given a death sentence."

"Because I had," said Ila. "In a way. She knew about me. About the Pull. She's known for years." She set the mug down on the rail, very slowly, and straightened. "She offered me a job. And then she asked me to steal the chart. And I said no."

"You said no."

"I said no, Tamsin."

"Why should I believe you?"

It was an ugly thing to say. She heard it fall out of her mouth and lie there, and wished it back. But she had said it, and it hung on the air between them like smoke, and she did not take it back.

Ila's face did not change. But something in her eyes went very quiet.

"I don't know," she said. "I don't know why you should. I've given you no reason. I've lied to you and left you and made a mess of everything that matters, and I haven't the right to ask you to trust a word I say." She drew a long breath. "But I've never lied about this. Not once. I swear it on everything I have. I told no one. Not Corra. Not Odo. Not a single living soul."

"You expect me to."

"I expect nothing."

"Then why."

"Because it's true," said Ila. "And because I think you know it is."

They stood a yard apart, in the amber light.

The silence stretched. Down on the quay, a boy was whistling. The gulls cried. Somewhere in the engine room, Odo's voice rose in a slow gruff snatch of song, and broke off, and began again.

She was so close. It was the closeness that undid her. She could see the faint pulse in Ila's throat. She could see the shadow of her lashes on her cheek, and the fine gold hairs at her temple, and the way her mouth trembled at one corner, a little, as if she were holding back a word. She could smell her. Salt and sun and the faint sweet green of the soap Odo kept in the galley. It filled her head like wine.

She knew. That was the thing. She had known the moment Ila said it. She had always been able to tell, with a sort of animal certainty, when Ila was lying. It had been one of the first things she learned about her. A tiny flick of the eyes, a small intake of breath, a tension in the left shoulder. She had watched for it all her life.

There was nothing. There was only a plain, tired, steady gaze, and a pair of open hands.

"Damn it," she said, quietly.

"I'm sorry?"

"I believe you."

Ila let out a breath. It shook.

"I believe you," Tamsin said again, and hated herself a little for it. She hated that she had been so quick to doubt, and so slow to see. She hated the cold tight sensation of having been, for ten long minutes, wholly and completely wrong. "I should have known. I'm sorry."

"It's all right."

"It isn't. I accused you."

"You were frightened."

"I wasn't."

"You were," said Ila. She said it gently. She lifted one hand, very slightly, and let it fall. "It's all right to be."

Tamsin looked at her.

It would have been so easy. She was aware of it, as one is aware of a drop beneath one's feet. A step, a word, a small crumbling of resolve. She stood at the edge of it with her heart in her mouth and every muscle drawn tight, and did not take it.

"We need a truce," she said instead.

"A truce."

"The two of us. We can't go on like this. It's a hazard to the crew and an embarrassment to me." She folded her arms. "I propose a settlement. We don't talk about the chart. We don't talk about last night. We don't talk about anything that happened in the cabin, or the orchard, or the Shoal. We're pilot and captain. We do the work. We keep it simple."

"That sounds."

"Sensible."

"Impossible."

"It's merely difficult."

"Tamsin." Ila said her name with a kind of desperate gentleness. "I don't think we can."

"We can try."

"And if it doesn't work?"

"Then we'll try harder." She held out a hand. "Agreed?"

Ila looked at it.

For a long moment, she did not move. Her eyes traveled from Tamsin's palm to her face, and back again, as though reading some fine print in a contract. There was a sad, wry, wondering look on her face, as of a person who has been asked to sign something she knows will not hold, and knows she is going to sign it anyway.

She took the hand.

It was a brief clasp. A firm shake, in the manner of two colleagues. It lasted perhaps two seconds. Tamsin counted every one of them. She felt the warmth of the fingers, and the roughness of the callus, and the hard small circle of the brass ring against her knuckle. She felt the whole hot weight of what she was not saying.

Then she let go, and put her hand in her pocket, and balled it into a fist.

* * * It was Juno who noticed the sky.

He had come up on deck for a smoke he was not supposed to be having. He stood at the stern rail with a thin cigarette cupped in one hand, trying to look inconspicuous, and he said, in an odd high voice, "Captain, you might want to see this."

She turned.

The sunset had gone strange. A moment ago it had been a clean amber glow, laid like gold leaf across the water. Now, in the west, a dark bar of cloud was climbing the horizon with sinister speed. It was a deep bruised purple, edged in sulfur yellow. It rose as she watched, swelling, spreading, boiling up against the brass of the sky like ink spilled in water. A cold breath of wind rippled across the harbor, and every flag on every mast stood out straight.

"That's not in the forecast," said Ila, beside her.

"No."

"Where did it come from?"

"Out of the deep." Tamsin did not take her eyes from the horizon. Her voice was flat. "That's an offshore squall line. A big one. It must have been building for days. It hasn't shown on the buoys because it's been sitting out past the edge of the array."

"How long do we have?"

"A day. Perhaps less."

"And the next Open Tide?"

"Falls the day after tomorrow," Tamsin said. "At dawn."

She felt, rather than saw, Ila turn her head.

They stood together at the rail, side by side, in the rising wind, and watched the clouds climb. The light had gone a lurid orange. The harbor lay unnaturally still, holding its breath. A single gull flew low across the water, crying, and then another, and then a long wild scatter of them, fleeing inland in a cloud.

It was going to be a bad one. She knew it as a sailor knows these things. A cold crawling feeling at the back of the neck. A tightening in the lungs. A voice, very small and clear, that said: whatever you have been avoiding, whatever you have been afraid to look at, it is about to arrive.

"Tamsin," said Ila.

"Yes?"

"I don't think this is a squall."

"What do you think it is?"

"I think it's the sea." She said it slowly, in a low, strange voice. "I think it's coming for something."

Tamsin did not answer.

She stood with her hands on the cold rail and the wind snatching at her braid, and looked into the heart of the storm. Behind her, in her cabin, in its leather tube, the chart gave a low, soft, trembling hum, like a bell struck far away. She felt it in her bones.

And beside her, a handbreadth away, close enough to touch, Ila stood with her face turned to the dark, and her lips moving soundlessly, and her hand closed tight around the brass ring on her thumb.

She was counting. Tamsin was certain of it.

Counting days.