Vessel

Sagittarius I Mission ^{DAY 1138, ONE DAY AFTER THE EVENT TRAPPIST-1F TWILIGHT LANDING AREA, ON BOARD SAGITTARIUS}

Alone.

No human had ever been as alone as Catherine was. She had an entire planet to herself.

Since the explosion, she’d been trying to figure out what happened. Had Tom set a fire? Stayed behind in it to die with the others? The command center was in the middle of the Habitat. The chances that he could have set a fire and gotten out in time… No, she had to assume everyone was dead.

She was no closer to any answers than she’d been a day ago.

She sat in the command module of Sagittarius, eating a cold MRE out of the pouch as she stared blankly out the windshield. Through it, she saw the vast rock formations of TRAPPIST-1f, glinting in the reflected light of her sister planets. The soil was the color of old, dried blood in this light.

Survival was the best thing she could manage right now. She wanted to make a plan to get home, but was there even any point? How was she going to fly back all by herself?

The comm screen beeped loudly and Catherine gave a small scream, jumping out of her chair. She was just about to write it off as her imagination, but then it beeped again, and she thumbed the receiver.

The screen flashed just two words: SURRENDER, CATHERINE.

Her makeshift dinner threatened to come back up her throat, stopped only by the fear that constricted it. She leaned in to the mic. “Who the hell is this? Tom? Is that you?” Her heart pounded so hard that it only increased the sick feeling in her belly, and she swallowed the rush of saliva in her mouth.

The screen flashed again. GIVE UP. GIVE IN. SURRENDER.

Fuck that. “Fuck you.” She enunciated clearly into the mic. “Whoever you are, if you want me, you’ll have to come and get me.”

She rubbed her mouth with the back of her hand, staring at the comms, waiting to see if there was an answer. It was Tom. It had to be Tom. But how could he have gotten out of the Habitat?

Maybe he’d lied when he’d said he was messaging her from inside. If nothing else, it was clear that he’d wanted her to stay inside so she’d die with the others. But if he was outside in a suit, why didn’t she see him when she came out?

The others were dead; she was sure of it. Once the fire had burned itself out, she’d explored the ruined Habitat. She’d found at least three bodies, but otherwise there hadn’t been much to identify; the fire had burned hot and fast in the Habitat’s oxygen-rich atmosphere. When no one else turned up, she made the logical assumption that she was the sole survivor.

I have to go home. I have to tell the others what happened, if nothing else.

Except… what could she tell them?

She stared at the comm screen while she thought. At one point she checked the message log and confirmed that yes, those messages had actually come in.

Okay. If she was going to go home, leaving was going to take some preparation. The ship itself wasn’t stocked with enough supplies for the long trip back. There was a supply shed on the far side of the landing area, on the other side of the Habitat—far enough to have been untouched by the blast. She’d have to raid and transport things one rover-load at a time. Thank God the second rover hadn’t been close enough to the Habitat to be destroyed, too.

After the first round of messages, the comms had pinged throughout the night, destroying any chance Catherine had of restful sleep. No matter how hard she tried to convince herself that she’d imagined the whole thing, the string of messages telling her to surrender was real. She’d deleted them in a fit of fear and bad judgment. It wasn’t supposed to be possible to delete any of the comm records, but Tom had shown her how to bypass those protocols, showing off for her with a cheeky grin.

Tom. He was still out there, and he expected her to surrender.

There was a tiny cache of weapons on Sagittarius, intended for protection against any unfriendly fauna on TRAPPIST-1f. When there had been no fauna to be found, those weapons—modified roughly from standard handguns to fire in different atmospheres—had been locked up shipboard. Ava had confessed to Catherine one night that NASA had also meant for those weapons to serve as a last-ditch solution for the crew, should the worst happen. One usage NASA probably hadn’t anticipated for those guns was for the crew to protect themselves against one of their own. But the guns were locked up, and she had no real way to get to them. Ava had been the only one with the passcodes.

“Okay. Okay. No guns, then. Fine.” Ah, well, the ability to improvise solutions in a crisis was one reason NASA had chosen them all, wasn’t it?

No weapons at all, and she still needed to start getting things together. She grabbed the tool kit from the ship’s storage area and slid a heavy wrench into a pocket of her jumpsuit. It might be useless as a weapon, but the weight of it made her feel better.

She drove the rover across the landing zone to the storage shed and started gathering some of the supplies. The entire time she worked, hauling crates onto the rover’s storage rack, the back of her neck prickled. Was Tom out there, watching her?

While she was in the shed, she heard a thunderous crash outside, and ran out to see all her carefully stacked crates spilled to the ground.

It was Tom.

He was coming at her from around the rover. His expression was utterly blank, slack-jawed. One side of his face had livid burn marks on the cheek. There was no light in his eyes at all, almost as if he weren’t even looking at her.

“Tom. Come on, it’s me. It’s Catherine.”

He stopped, and his eyes focused, fixing on her, still dead and cold.

“We have to work together to get home.”

“Surrender.” His voice was flat, unemotional.

He started toward her again, at a steady, relentless walk. She pulled the wrench from her pocket. “Stop. I don’t want to hurt you.”

Tom didn’t stop. But Catherine couldn’t make herself swing the wrench at his head. At the last second she spun and tried to flee, but he caught her by the shoulder, reaching for her throat. His fingers burned hot through the material of her suit as they closed around her neck.

Catherine fell back on her training. She fought hard and dirty, slamming a foot into Tom’s, clawing at his hands. Finally she hit backward with the wrench, connecting with his skull through his hood. Tom grunted and his hands loosened from her neck. She fled, leaving the rover behind for now. She looked back to see Tom still on his feet, blood on his head and his hand. He began to chase her.

Once she was in the shadow of the rocks, she ducked and wove through them, hiding behind one to listen for his footsteps.

He was easy to hear, trampling over the ground without any attempt at stealth.

She waited for what felt like hours, until the footsteps receded and all she heard was silence. She had no way of knowing where he was, if he was searching for her in the distance or lying in wait. All she knew was that she couldn’t stay here. Slowly, quietly, she pushed herself upright, the wrench clamped tight in her fist.

Silence.

She didn’t see Tom. Couldn’t hear him. This was her chance.

She sprinted back for the rover, her heart thudding in her chest. Everything was just as she’d left it. The metal crates were still intact. She shoved them up onto the rover, less careful about stacking than before, no longer interested in loading as much as she could in one trip. The entire time, her skin crawled, waiting, listening for the sound of Tom. Despite everything, she didn’t know if she could kill him.

She climbed into the rover and started it up, pushing the little motor as fast as it would go back to the ship. Even if he pursued her, the ship was far enough away, and she had enough of a head start, to give her time to unload the rover before he could reach her.

By the time she finished loading the crates on board Sagittarius, Catherine was exhausted and sweaty. Not to mention starving. She sealed up the ship, finally able to relax a bit knowing that Tom couldn’t reach her in here. Whatever had happened to him, he seemed too far gone for her to get him back.

The question was, did that mean she was going to leave him behind when she left?

After she cleaned up, luxuriating in the feel of clean clothes, she started pulling together dinner. She was so hungry that waiting for everything to heat up felt like an eternity. She was just about to sit down in the galley when the comms started pinging again.

Catherine froze, halfway between sitting and standing, her appetite vanishing. With her stomach twisting in knots, she went to the cockpit, expecting to see the demand to surrender flash on the screen again. Instead, she got Tom’s voice.

“Sagittarius, this is Tom Wetherbee; if you’re there, come in. If anyone’s alive, please come in. Someone must be out there. The ship is locked; I couldn’t get in.”

A chill shot down Catherine’s spine.

“Sagittarius, I’m wounded. My suit’s torn; I’ve got some burns. I think something scratched me. Please help me.”

Part of her mind insisted this was a trick, told her not to answer him. He sounded so desperate, though. So terrified.

She settled in front of the console. “Tom, it’s Catherine.”

“Oh thank God!” he cried. “What happened? The Habitat—it’s gone.”

“Where are you?”

“I’m in the storage shed,” Tom said. “The ship was locked, so I thought someone must be inside… Tell me what happened!”

“You don’t remember the explosion?”

“Jesus. No. Where is everyone?”

I don’t know what I did last night…

Catherine’s mouth was dry when she tried to swallow. “They’re dead, Tom. I thought you were dead, too.”

There was silence over the comms, and when he came back on, it sounded as if he were barely holding on to himself. “All of them? No. Oh God. How much time have I lost, Catherine?”

“It’s been a day since the explosion. How did you get out?”

“I don’t know. Last thing I remember I was under the console in the command center, elbow-deep in some wiring, trying to figure out how things had gotten so fucked up. Then I’m sitting in the middle of nowhere burned and bleeding.” He paused. “I think something attacked me.”

Did he really not remember? Or was this all a ploy to draw her out? “You tried to kill me today. You’ve been sending me threatening comm messages.”

“That’s ridiculous. I would never— I could never hurt you.” The betrayal in his voice sounded so real that she wanted to believe it.

“I’ve got the bruises to prove it.”

“I don’t remember that!” The quaver in his voice also sounded real. “Cath, I think I’m getting a fever.”

“I can’t let you back on the ship. You’ve got to be quarantined, Tom.” Even if I trusted you, which I don’t.

Tom’s voice grew hard. “You’re going to leave me behind. You’re going to just let me die.”

“No.” Yes. Maybe. “Look, there’s plenty of food and supplies still in the storage shed. I’ll leave the antibiotics and painkillers you’re missing outside the ship. I-I’ll wait through your quarantine with you.”

“You’re a shit liar, Wells.”

“Hang on.” Catherine ran to the infirmary and grabbed the promised medication. If he was lying and was right outside instead of in the storage shed, she was taking an enormous risk, but she had to. Even if she wasn’t sure she could trust him, she needed to be trustworthy herself. She opened the ship’s main hatch. Tom was nowhere to be seen. She put the containers just outside the hatch before ducking back in and resealing everything. When she got back to the comms, she said, “The meds are waiting for you now.”

“I don’t know if I can walk that far.”

“You tried to choke me. I’m not coming to you.”

“Fine. God, you always were a heartless bitch.” That was real, even if the tears had been fake. “If I die, my blood is on your hands.”

Yeah, well, she knew that much.

“If the meds work, we’ll talk.” Then she shut off the mic and walked away.

There were no other messages that night.

Exhausted as she was, Catherine barely managed to sleep. When the sun came up, she crept to the main hatch.

What she saw shocked her, and, if she was honest, touched her a little. The meds she’d left were gone, and parked in front of the ship was the rover, loaded with supplies. Judging from the other crates stacked around it, there were plenty of supplies for a return trip home. Tom must have spent all night making trips back and forth.

Was it a trick? Then she saw the message scratched in the dirt:

He was willing to wait outside the ship for two days to see if he came down with something or, like Catherine, stayed well. Even if she didn’t trust him, she couldn’t turn down what he was offering. The supplies he left weren’t tampered with. The seals on all the crates were still intact. He couldn’t have gotten to the contents.

Faced with the prospect of trying to get a different batch of supplies and possibly having to fight off Tom again, Catherine decided to take the chance. She started loading the crates. It took the better part of a day, hauling things between the rover and the open hatch. By the time she was finished, she’d reached a decision: She’d wait forty-eight hours. If Tom was still alive, she’d worry about making a final decision then. In the meantime, she’d stay locked in the ship where it was safe. With the long trip back home, a couple more days wouldn’t make a difference one way or another.