Now the Helmsman tipped forward, as if rocking. He spoke, and his voice was faint, as if coming from far away.

“Jiang Ling. I dream I am at home, in my villa here in Beijing, with my family and associates. News arrives. On the fringe of the city, there is an odd outbreak of a respiratory disease. Hundreds of citizens present themselves to the hospitals gasping for breath. The first symptoms include vomiting, fever, a choking cough and labored breathing. Antibiotics appear to contain the disease. Without antibiotics, death from hemorrhage, respiratory failure or toxic shock follows in a few days. It kills more than ninety percent of its victims. The doctors struggle to diagnose this bizarre, unusual illness.

“People start to die, in large numbers.

“At last the doctors understand. The disease is spread by spores — spores polluting the air of the city, thousands of them entering the lungs with every breath — and the spores cross the lining of the lungs and travel to the lymph nodes, where they germinate, multiply and spread to other tissues, releasing toxins as they go.

“Public health officials try to understand where the spores come from and which direction they are spreading. But this takes time; and we have no more time. Rumors begin to spread that supplies of antibiotics have run out.

“Other rumors state that only some racial groups are affected by the disease: specifically, Han.

“I appear on softscreens, in Beijing and across the nation, and I caution against panic. But then news is brought to me that even my family has been exposed, even myself…”

He seemed to be looking at her, but his eyes were so vague and discolored she could not be certain. “Jiang Ling, I am describing an attack by the anthrax bacillus — or rather, a strain of it genetically engineered to strike at specific population groups. My advisers inform me that it would take a mere two hundred pounds of spores to destroy three million people in a city like this. And, my advisers say, such gruesome weapons are even now under preparation for use against us in secret laboratories in the United States…”

Jiang, horrified, thought of the America she had glimpsed: large, complex, confused, fragmenting, frightened. And she thought of some of the Western leaders she had met, for instance the chilling General Hartle: a grisly mirror image of the Helmsman, another old man clinging to the levers of power, continually reenacting the paranoia of his youth.

Was such scheming possible there?

Yes, she decided.

“But,” she asked, “what is my assignment, sir?”

The Great Helmsman lifted his hand, his bony wrist protruding from the soft fabric of his Mao suit, his fingers thin as dried twigs, and he beckoned to her.

She stepped forward and, encouraged by the Helmsman’s daughter, she leaned down and placed her face close to his. Close up, his skin did not have the alien texture she had perceived from a greater distance; it was clearly human, but brown with age, as brown as the earth, and riven with wrinkles and cracks, distended pores like the craters of the Moon. She had an impulse to reach out and touch it, to feel the faint warmth which must still pump beneath that battered surface.

His eyes, embedded in their black sockets, were like pearls, grey, moist, formless. His breath smelt, oddly, of milk.

“Yingzhen zhike,” he said. “Poisonous wine. We must drink poisonous wine to slake our thirst. That is your assignment, Jiang Ling. You must sip the wine, now, for all of us…”

His voice was as dry, she thought, as the scratch of a leaf along the bed of an ancient Martian canal.

Benacerraf was standing on a shallow, undulating beach. Overhead, grey-brown methane cumulus clouds crowded the sky.

The black meniscus of Clear Lake, flat and still, swept all the way to a horizon that was nearby and sharply curving, dimly obscured by the continuous, burnt-orange drizzle of organic sediment. To left and right, Benacerraf could make out the mountainous walls of the enclosing crater, like lines of steep, irregular hillocks, their erosion channels stained by gumbo streaks, their profiles softened by the slow relaxation of the bedrock ice. Under the uniform orange glow which suffused everything, the lake’s liquid ethane sat like a basinful of crude oil, thirty miles across.

The lighting — orange above, black below — and the sharp curvature of this small world were disconcerting. It was as if she was looking through a fish-eye lens, like the Apollo periscope, which made the ground bulge upwards towards her, distorted by a rendering in false colors.

She wondered how long it would take for the lack of blue and green in this landscape to drive her crazy.

Rosenberg had been hoping that they might find the tholin washed away, exposing a rim of bedrock water ice, reasonably accessible. It hadn’t worked out that way. These ancient, frozen coastlines were eroded by the slow action of waves — in fact Benacerraf could see some evidence of wave action; at the very edge of the liquid there were parallel streaks of crusty, foamy deposit, like the debris of some industrial pollutant, washed up over the raw tholin — but the drizzle of tholins from the air evidently fell more thickly than the waves could wash them away.

This was really just a down-sloping extension of the sludgy gumbo-coated icescape she’d become used to, the purple-brown sheen of tholin continuing all the way to the edge of the ethane lake and beyond.

And yet this was, nevertheless, a beach: one in its morphology with that other beach at Canaveral, a billion miles away, from which she had launched. And there was the same air of disjointedness she had noticed at beaches on Earth — at the interface between two different media, the sea and the land, where erosion and decay worked to reduce mountains and cliffs to a uniform, muddy mediocrity.

And besides, she thought, maybe this wasn’t so unearthly after all. A few billion years back — give or take a couple of hundred degrees — it mightn’t have been so different to stand on the beaches of primeval Earth, to look out on a similar ocean of sludgy, prebiotic organic soup. It was on a beach like this, she thought, that some proto-amphibian ancestor of mine first crawled out. She had come full circle.

Rosenberg touched her shoulder; she could barely feel the weight of his hand through the layers of her suit. “Weather forecast for all you nautical types,” he said. “Haze.”

“Funny, Rosenberg.”

“So. You ready to go?”

Ready, she thought, to go sailing: on a horseshoe-shaped lake of paraffin, for all the world like a character in an Edward Lear poem. I want to be back in Seattle.

She padded back up the shallow slope of the beach to the boat. She was wearing snowshoes, as they called them: big curving plates of Command Module hull metal, strapped to her blue boots. The snowshoes kept her pretty much on top of the sticky gumbo. She had worked out a way of walking that involved sliding the snowshoes forward first, as if scraping mud off the soles, to free them of the clinging gumbo.

The “boat” was simply the base of Mott’s Command Module, Jitterbug. Benacerraf and Rosenberg had cut away the external shell of the double-skinned Module a couple of feet above the rounded lip of the heatshield. What they ended up with was a round, shallow bowl with a turned-up rim, something like a big dog-food dish, thirteen feet across. The orifices which had once contained the nozzles of reaction control engines were round, gaping wounds in the shallow walls. Rosenberg had plugged all but one of these; to the last he had fixed a steel cable. Atmospheric entry scorch marks still spread from the heatshield lip up and over the low walls of the boat. The wall had been etched with a scale, gradations inches apart, so they could measure the draft of the boat in Clear Lake. Its interior was cluttered up with the equipment Benacerraf was going to need, out on the ethane.