He slung the weapon and checked the HE warhead attached to his hip. The timer and detonator looked undamaged.

John faced a sealed set of sliding pressure doors. It was smooth and soft to his touch. It could have been made of metal or plastic... or could have been alive, for all he knew.

He and Sam grabbed either side and pulled, strained, and then the mechanism gave and the doors released. There was a hiss of atmosphere, a dark hallway beyond. They entered in formation—covering each other’s blind spots.

The ceiling was three meters high. It made John feel small.

“You think they need all this space because they’re so large?” Kelly asked.

“We’ll know soon,” he told her.

They crouched, weapons at the ready, and moved slowly down the corridor, John and Kelly in front. They rounded a corner and stopped at another set of pressure doors. John grabbed the seam.

“Hang on,” Kelly said. She knelt next to a pad with nine buttons. Each button was inscribed with runic alien script. “These characters are strange, but one of them has to open this.” She touched one and it lit, then she keyed another. Gas hissed into the corridor. “At least the pressure is equalized,” she said.

John double-checked sensors. Nothing... though the alien metal inside the ship could be blocking the scans.

“Try another,” Sam said.

She did—and the doors slid apart.

The room was inhabited.

An alien creature stood a meter and half tall, a biped. Its knobby, scaled skin was a sickly, mottled yellow; purple and yellow fins ran along the crest of its skull and its forearms. Glittering, bulbous eyes protruded from skull-like hollows in the alien’s elongated head.

The Master Chief had read the UNSC’s first contact scenarios—they called for cautious attempts at communication. He couldn’t imagine communicating with something like this... thing. It reminded him of the carrion birds on Reach—vicious and unclean.

The creature stood there, frozen for a moment—staring at the human interlopers. Then it screeched and reached for something on its belt, its movements darting and birdlike.

The Spartans shouldered their weapons and fired a trio of bursts with pinpoint accuracy.

Armor-piercing rounds tore into the creature, shredding its chest and head. It crumpled into a heap without a sound, dead before it hit the deck. Thick blood oozed from the corpse. “That was easy,” Sam remarked. He nudged the creature with his boot. “They sure aren’t as tough as their ships.”

“Let’s hope it stays that way,” John replied.

“I’m getting a radiation reading this way,” Kelly said. She gestured deeper into the vessel.

They continued down the corridor and took a side branch. Kelly dropped a NAV marker, and its double blue triangle pulsed once on their heads-up displays.

They stopped at another set of pressure doors. Sam and John took up flanking positions to cover her. Kelly punched the same buttons she had punched before and the doors slid apart.

Another of the creatures was there. It stood in a circular room with crystalline control panels and a large window. This time, however, the vulture-headed creature didn’t scream or look particularly surprised.

This one looked angry.

The creature held a clawlike device in its hand—leveled at John.

John and Kelly fired. Bullets filled the air and pinged off a silver shimmering barrier in front of the creature.

A bolt of blue heat blasted from the claw. The blast was similar to the plasma that had hit the Commonwealth... and boiled a third of it away.

Sam dove forward and knocked John out of the blast’s path; the energy burst caught Sam in the side. The reflective coating of his MJOLNIR armor flared. He fell clutching his side, but still managed to fire his weapon.

John and Kelly rolled on their backs and sprayed gunfire at the creature.

Bullets peppered the alien—each one bounced and ricocheted off the energy shield.

John glanced at his ammo counter—half gone.

“Keep firing,” he ordered.

The alien kept up a stream of answering fire—energy blasts hammered into Sam, who fell to the deck, his weapon empty.

John charged forward and slammed his foot into the alien’s shield and knocked it out of line. He jammed the barrel of his rifle into the alien’s screeching mouth and squeezed the trigger.

The armor-piercing rounds punctured the alien and spattered the back wall with blood and bits of bone.

John rose and helped Sam up.

“I’m okay,” Sam said, holding his side and grimacing. “Just a little singed.” The reflective coating on his armor was blackened.

“You sure?”

Sam waved him away.

John paused over the remaining bits of the alien. He spotted a glint of metal, an armguard, and he picked it up. He tapped one of three buttons on the device, but nothing happened. He strapped in onto his forearm. Dr. Halsey might find it useful.

They entered the room. The large window was a half-meter thick. It overlooked a large chamber that descended three decks. A cylinder ran the length of the chamber and red light pulsed along its length, like a liquid sloshing back and forth.

Under the window, on their side, rested a smooth angled surface—perhaps a control panel? On its surface were tiny symbols: glowing green dots, bars, and squares.

“That’s got to be the source of the radiation,” Kelly said, and pointed to the chamber beyond. “Their reactor... or maybe a weapons system.”

Another alien marched near the cylinder. It spotted John. A silver shimmer appeared around it. It screeched and wobbled in alarm, then scrambled for cover.

“Trouble,” John said.

“I’ve got an idea.” Sam limped forward. “Hand me those warheads.” John did as he asked, so did Kelly. “We shoot out that window, set the timers on the warheads, and toss them down there. That should start the party.”

“Let’s do it before they call in reinforcements,” John said.

They turned and fired at the crystal. It crackled, splintered, then shattered.

“Toss those warheads,” Sam said, “and let’s get out of here.”

John set the timers. “Three minutes,” he said. “That’ll give us just enough time to get topside and get away.”

He turned to Sam. “You’ll have to stay and hold them off. That’s an order.”

“What are you talking about?” Kelly said.

“Sam knows.”

Sam nodded. “I think I can hold them off that long.” He looked at John and then Kelly. He turned and showed them the burn in the side of his suit. There was a hole the size of his fist, and beneath that, the skin was blackened and cracked. He smiled, but his teeth were gritted in pain.

“That’s nothing,” Kelly said. “We’ll get you patched up in no time. Once we get back—” Her mouth slowly dropped open.

“Exactly,” Sam whispered. “Getting back is going to be a problem for me.”

“The hole.” John reached out to touch it. “We don’t have any way to seal it.”

Kelly shook her head.

“If I step off this boat, I’m dead from the decompression,” Sam said, and shrugged.

“No,” Kelly growled. “No—everyone gets out alive. We don’t leave teammates behind.”

“He has his orders,” John told Kelly.

“You’ve got to leave me,” Sam said softly to Kelly. “And don’t tell me you’ll give me your suit. It took those techs on Damascus fifteen minutes to fit us. I wouldn’t even know where to start to unzip this thing.”

John looked to the deck. The Chief had told him he’d have to send men to their deaths. He didn’t tell him it would feel like this.

“Don’t waste time talking,” Sam said. “Our new friends aren’t going to wait for us while we figure this out.” He started the timers. “There. It’s decided.” A three-minute countdown appeared in the corner of their heads-up displays. “Now—get going, you two.”

John clasped Sam’s hand and squeezed it.

Kelly hesitated, then saluted.