Act I

The sun was the colour of a dying ember on the morning the River Engine left New Orleans. It hung low in the sky, swollen and red, casting long shadows across the flooded streets. The water had reached the second story of the French Quarter by dawn, and by noon it would reach the third. But on this morning, it was still possible to walk — if you knew which rooftops to use and which bridges were still standing.

Captain Jeremiah Beauchamp stood on the deck of his barge and watched the sun. He had seen this sun before — not this particular sun, but suns like it. He had seen them from the deck of nuclear submarines, buried beneath the Atlantic, waiting for orders that never came. He had seen them from the deck of transport ships, carrying soldiers to wars he did not believe in. He had seen them from the deck of this barge, moored on the Mississippi for thirty years, watching the river rise and fall and rise again.

But this sun was different. This sun was dying.

Sister Mary Agnes came onto the deck with the children. Twelve of them — a mixed group, some from New Orleans, some from communities further upstream that had been abandoned as the flooding consumed them. They ranged in age from six to sixteen. They wore coats that were too thin and shoes that were too small. They stood on the deck and looked at the red sun and did not ask questions. Children who had lived through the flooding had learned that questions were worse than answers.

"Sister," Jeremiah said, "how many?"

"Twelve," she said. "Some are younger than I'd like for this kind of journey. But there's nowhere else for them to go."

"There's nowhere else for any of us to go," Jeremiah said. He looked at the river. The Mississippi was wide and brown and slow, its surface covered with debris — pieces of roofs, abandoned furniture, the occasional object that someone had tried to float away and failed.

"Can your boat make it to the Missouri?" a boy of about thirteen asked. He was Black, barefoot, with a face that was too old for his body.

"It can make it to the Arkansas," Jeremiah said. "Past that, you'll need something smaller."

"Will we make it to the Ozarks?" a girl of about eight asked. She was white, Creole, with dark hair pulled back in a braid. She held a small stuffed rabbit by the ear.

Jeremiah looked at the sun. It was redder than it should have been. The sky was orange at the edges, yellow at the centre, and the light had a quality that he had never seen before — a weight, a pressure, as though the atmosphere itself was thickening.

"No," he said. "We won't make it to the Ozarks. But we'll get as far as we can."

Act II

The River Engine was a barge that Jeremiah had converted over thirty years. It had been a simple cargo barge — flat-bottomed, square-nosed, built for hauling gravel and timber. Jeremiah had added a cabin (a single room with a bunk, a stove, and a head), a solar panel array (scavenged from a defunct satellite), and an engine (a diesel V8 that he had rebuilt from parts). It was not fast. It was not comfortable. But it was seaworthy, and it was his.

They departed at noon. The floodwaters carried them out of the French Quarter and into the main channel of the Mississippi. The city rose around them — submerged, silent, its streets turned to rivers and its buildings turned to islands. St. Louis Cathedral still stood, its spires piercing the orange sky like a finger pointing at a dying god.

Preacher Tom Delacroix joined them two days later at the Louisiana-Arkansas border. He appeared on the river like a figure from a painting — a man in a canvas coat and a wide-brimmed hat, paddling a canoe that seemed absurdly small next to the barge. He called out from the water: "You going north, Captain?"

Jeremiah lowered a rope ladder. Tom climbed aboard and sat on the deck, dripping, and told them what they needed to know. The river was worst north of here — the levees had failed in three places, and entire counties were underwater. The heat was increasing. The sun was getting hotter. Nobody knew why.

"There ain't nothing north of here but water and fire," Tom said. "You turn back now, I won't blame you."

Jeremiah shook his head. "We're going as far as we can."

Tom nodded. He stayed for one night, sitting on the deck with Jeremiah, drinking whiskey from a tin cup, and telling stories about the Mississippi as it used to be — clean, navigable, alive. In the morning, he paddled away. The children watched him go with the blank expressions of children who have learned that people leave and do not return.

Act III

They reached the Mississippi-Missouri confluence three days before the sun's helium flash reached Earth. The heat was unbearable now — daytime temperatures exceeding 110 degrees Fahrenheit. The river was shrinking, evaporating faster than it could be replenished. The debris that had clogged the channel was gone, burned away or carried downstream by floods that were themselves dying.

The children were dehydrated and exhausted. The youngest, a girl of six named Rose, slept most of the time, wrapped in a wet cloth on the deck. Jeremiah carried her when she could not walk. He gave his water ration to her when his own was low. He did not notice that he was doing it.

On the last evening, he gathered the children on the deck. The sun was enormous — a red orb filling a third of the sky. The heat radiating from it was visible as a shimmer, a distortion of the air that made the horizon waver.

"I can't go further," he said. "The Missouri is too shallow for this boat. But I've prepared something for you."

He pointed to a catamaran moored alongside the barge — a smaller vessel, built for speed and shallow draft. It was loaded with supplies — food, water, a compass, a radio that would not work but he gave it to them anyway.

"This will take you to the high ground," he said. "Follow the Missouri until you find it. Go north. Keep going north."

One by one, the children boarded the catamaran. Each one shook his hand. Each one said something — thank you, Captain, God bless you, don't forget us.

The last to board was Ruby, sixteen years old, the oldest of the group. She stood on the edge of the catamaran and looked at him.

"Come with us," she said.

He shook his head. "Someone has to steer the River Engine."

She nodded. She understood. She boarded the catamaran, and the children pushed off, and the current carried them north into the dying light.

Jeremiah turned the River Engine south.

Act IV

He docked the barge in what remained of the French Quarter and climbed onto the levee. The sun was setting — or dying. It was hard to tell the difference. It hung above the flooded city like a red eye, watching, indifferent, magnificent.

He thought about his life — his thirty years in the Navy, denied promotion because of the colour of his skin. His thirty years on the river, avoiding the future, avoiding people, avoiding the things he could not change. He had been a captain once — of a submarine, of a river, of twelve children on the last journey they would ever take. And then he had been nothing.

But those children were alive. They were heading north, toward the last habitable land on Earth, carrying with them the knowledge that an old Black man in a flooded city had chosen to help them instead of saving himself.

That was enough.

The sun dipped below the horizon. The sky was a colour he had never seen — a deep, burning gold that made the flooded streets of the French Quarter look like molten metal. He stood on the levee and watched it and breathed the hot air and felt the river beneath his feet.

The helium flash reached Earth three hours later. The atmosphere ignited. The river boiled. The city vanished.

But the catamaran had already been gone for eight hours, carrying twelve children toward a north that might not exist, propelled by the last act of a man who had spent his life running from mountains and ended his life facing the sun.

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