Amos was waiting for her outside the airlock when she arrived. He wore his Martian-made light armor and carried his oversized gun. Prax rushed into the compartment a few minutes later, still struggling to get into his borrowed gear. He looked like a boy wearing his father’s shoes. While Amos helped him get buttoned up, Alex called down to the airlock and said, “Heading down. Hang on to something.”

Bobbie turned her boot mags to full, locking herself to the deck while the ship shifted under her. Amos and Prax both sat down on chairs that pulled out from the wall, and belted in.

“Let’s go over the plan one more time,” she said, calling up the aerial photos they’d shot of the facility. She patched into the Roci and threw the pictures onto a wall monitor. “This airlock is our entrance. If it’s locked, Amos will blast it with explosives to open the outer door. We need to get inside fast. Your armor isn’t going to protect you from the vicious radiation belt Io orbits in for long. Prax, you have the radio link Naomi rigged, so once we’re inside, you start looking for a network node to plug it into. We have no information about the layout of the base, so the faster we can get Naomi hacking their system, the faster we can find those kids.”

“I like the backup plan better,” Amos said.

“Backup plan?” Prax asked.

“The backup plan is I grab the first guy we see, and beat him until he tells us where the kids are.”

Prax nodded. “Okay. I like that one too.”

Bobbie ignored the macho posturing. Everyone dealt with pre-combat jitters in their own way. Bobbie preferred obsessive list making. But flexing and threats were good too. “Once we have a location, you guys move with all haste to the kids, while I ensure a clear path of egress.”

“Sounds good,” Amos said.

“Make no mistake,” Bobbie said. “Io is one of the worst places in the solar system. Tectonically unstable and radioactive as hell. Easy to see why they hid here, but do not underestimate the peril that just being on this shit moon carries.”

“Two minutes,” Alex said over the comm.

Bobbie took a deep breath. “And that isn’t the worst. These ass**les launched a couple hundred human-protomolecule hybrids at Mars. We can hope that they shot their entire wad, but I have a feeling they didn’t. We might very well run into one of those monsters once we get inside.”

She didn’t say, I’ve seen it in my dreams. It seemed counterproductive.

“If we see one, I deal with it. Amos, you almost got your captain killed blasting away at the one you found in the cargo bay. You try that shit with me, I’ll snap your arm off. Don’t test me.”

“Okay, chief,” Amos replied. “Don’t get your panties in a twist. I heard you.”

“One minute,” Alex said.

“There are Martian Marines controlling the perimeter, but they’ve been given the okay to let us in. If someone escapes past us, no need to apprehend them. The Marines will pick them up before they get far.”

“Thirty seconds.”

“Get ready,” Bobbie said, then pulled up her HUD’s suit status display. Everything was green, including the ammo indicator, which showed two thousand incendiary rounds.

The air sucked out of the airlock in a long, fading hiss, leaving only a thin wisp of atmosphere that would be the same density as Io’s own faint haze of sulfur. Before the ship hit the deck, Amos jumped up out of his chair and stood on his toes to put his helmet against hers. He yelled, “Give ’em hell, marine.”

The outer airlock door slid open, and Bobbie’s suit blatted a radiation alarm at her. It also helpfully informed her that the outside atmosphere was not capable of supporting life. She shoved Amos toward the open lock and then pushed Prax after him. “Go, go, go!”

Amos took off across the ground in a weird, hopping run, his breath panting in her ears over the radio link. Prax stayed close behind him and seemed more comfortable in the low gravity. He had no trouble keeping up. Bobbie climbed out of the Roci and then jumped in a long arc that took her about seven meters above the surface at its apex. She visually scanned the area while her suit reached out with radar and EM sensors, trying to pinpoint targets. Neither she nor it found any.

She hit the ground next to the lumbering Amos and hopped again, beating them both to the airlock door. She tapped the button and the outer door cycled open. Of course. Who locks their door on Io? No one is going to hike across a wasteland of molten silicon and sulfur to steal the family silver.

Amos plowed past her into the airlock, stopping for breath only once he was inside. Bobbie followed Prax in a second later, and she was about to tell Amos to cycle the airlock when her radio died.

She spun around, looking out across the surface of the moon for movement. Amos came up behind her and put his helmet against her back armor. When he yelled, it was barely audible. “What is it?”

Instead of yelling back, she stepped outside the airlock and pointed to Amos, then pointed at the inner door. She mimed a person walking with her fingers. Amos nodded at her with one hand, then moved back into the airlock and shut the outer door.

Whatever happened inside, it was up to Amos and Prax now. She wished them well.

She spotted the movement before her suit did. Something shifting against the sulfurous yellow background. Something not quite the same color. She tracked it with her eyes and had the suit hit it with a targeting laser. She wouldn’t lose track of it now. It might gobble radio waves, but the fact that she could see it meant that light bounced off it just fine.

It moved again. Not quickly, and staying close to the ground. If she hadn’t been looking right at it, she’d have missed the motion entirely. Being sneaky. Which probably meant it didn’t know she’d spotted it. Her suit’s laser range finder marked it as just over three hundred meters away. According to her theory, once it realized it had been spotted, it would charge her, moving in a straight line to try to grab and rip. If it couldn’t reach her quickly, it would try to throw things at her. And all she needed to do was hurt it until its program failed and it self-destructed. Lots of theories.

Time to test them out.

She aimed her gun at it. The suit helped her correct for deflection based on the range, but she was using ultrahigh velocity rounds on a moon with fractional gravity. Bullet drop at three hundred meters would be trivial. Even though there was no way the creature could see it through her helmet’s darkened visor, she blew it a kiss. “I’m back, sweetie. Come say hi to momma.”