Eagle Four lifted off from the cratered surface of a small asteroid, leaving behind an ad hoc ground station hastily built to shelter a mining crew for the two days the traveling moon remained in range of the mineral-rich space rock. That station was empty now, with only spent drill bits, discarded oxygen canisters, and drained power cells left behind.

In Eagle Four's belly, the last haul of bounty: iron, iridium, palladium, platinum, and magnesium. This was no pirate's treasure, but vital raw materials to be smelted into needed replacement parts for Moonbase Alpha.

Pete Irving sat in the cockpit across from his co-pilot, Ed Davis, both in the orange "pumpkin suits" that were uncomfortable but had been necessary when working on the asteroid's surface.

Paul Morrow's face and intense glare appeared on the flight console screen.

"Alpha to Eagle Four, do you copy?" came Morrow's voice from fifty thousand kilometers away.

Irving eyed the approaching moon through the port side cockpit window and thumbed the comm panel to open two-way communications.

"Four here, Alpha. We've got the last load and are on our way back to base."

"Standard approach Eagle Four. We're sending you to landing pad two. Computer is taking the stick."

Irving gave his co-pilot a sardonic glance and transmitted, "Say, Main Mission, are we getting overtime for this? Me and Ed here didn't sign up for mining detail."

Morrow was not amused. "You'll get what everyone else gets, Irving. Enjoy the ride."

"Right. See you in twenty minutes." Irving shut off the comm, pulled his hands away from the flight sticks, and said to Davis, "That man has no sense of humor."

Davis responded with a wry smirk.

A flash of light above the moon's horizon caught his eye.

"Say, Ed, did you see that?"

Davis leaned forward in his seat, but said nothing.

A pair of indicators flickered on the control console. "I've got something on the scanners."

Near the traveling moon, a vortex of red, yellow, and blue spinning like a whirlpool in space. A splash of magnificent color against a backdrop of pitch black.

"What is that?" Irving gasped.

The maelstrom collapsed upon itself and faded as fast as it had come. A solitary sparkle remained, emitting a golden yellow shine. Despite appearing small from their current vantage point, Irving estimated the object was five or six times larger than his Eagle...

... Main Mission came to life, the routine shattered by an anomaly appearing a few thousand kilometers above the moon's surface, visible not only to scanners and telescopes, but to the naked eye. First a storm of radiance, then a solitary entity.

The heart of Alpha Moonbase beat fast in response to the unexpected encounter. Staff turned their attention from coffee cups to consoles. Automated alarms warned of the newcomer.

Paul Morrow's face hardened as he checked the readout on his console and turned to Sandra Benes who, in her soft but sturdy voice, spoke the obvious: "Unknown object has appeared at orbital reference 337. Energy readings exceed instrument scale."

The work stations of Main Mission were arranged in a U-shape with David Kano's computer desk at the center. The tech specialist spun around his console and faced Morrow. "Object does not match any known spacecraft configuration."

Paul shook his head, annoyed. Comparing an object out here, in the depths of outer space, to their Earth-born catalog of space vehicles was as useful as trying to fish on the lunar surface.

"Paul. I have a visual. On the main board," Tanya Alexander said and the image of the intruder filled the main viewscreen.

It had a rough diamond shape, enhanced by a mesmerizing shroud of golden light. It could have been spinning, or perhaps the glittery envelope created that perception.

Paul punched a button on his communications console. "Commander Koenig to Main Mission. Urgent."

As he relayed that message, Alan Carter jogged into the cavernous room. "Paul. I saw it on the flight cameras. Do we know what it is? Where'd it come from?"

"You know what we know."

Carter's face drew long, and he asked, "Irving? Davis?"

Morrow transmitted, "Main Mission to Eagle Four, are you receiving?"

"Yeah, we hear you, Alpha. Are you seeing this? A real light show up here."

Carter bullied his way into the conversation. "Pete, what's your status? Stay clear of that thing."

"You can say that again. I'm not going anywhere near it."

Morrow eyed Carter with a stiff lip and communicated, "Computer is bringing you in. Giving you a wide berth."

The long rolling doors separating Main Mission from the commander's office slid open. Koenig and Professor Bergman—the latter holding a clip board—hurried down the stairs to Paul's side.

"What is it?"

"Unknown," Morrow said. "It came out of nowhere."

Sandra added, "Long range scanners did not detect its approach. There was a spatial anomaly and then... it was suddenly... there."

Cater didn't like puzzles, particularly with one of his flight crews in the air and especially with the payload on Irving's transporter. "Commander, whatever it is, we need that cargo. Half our Eagles are past their service lives. Pretty soon they won't fly unless we engineer spare parts."

Morrow growled, "The Eagles can wait. We need those metals for the power station and life support systems. That's the priority."

Bergman tapped his chin and interrupted yet another flare up of that ongoing argument: "I think we can deal with that later. Right now..." and he nodded toward the apparition filling the view screen.

Both Carter and Morrow turned a shade of red and bowed their heads.

From Eagle Four: "Alpha, hold on, we're receiving some kind of... wait a second, it's our computers. The X5 and the nav com are going haywire."

Carter hurried to a row of monitors below the main viewer. Two of those screens depicted the pilots' vital signs. Heart rate and respiration increased rapidly. He switched to a third one to display the onboard computer readouts. "What the devil is this?"

Squiggly lines, apparently random in their configuration, danced on the screen in a chaotic display.

Bergman mused, "Interesting."

Koenig said, "Someone tell me what that is."

Kano: "That pattern is not generated by computer. Commander, it is an external intrusion."

Morrow glared at the computer expert. "Eagle Four is on automatic guidance."

Koenig leaned in and toggled the transmitter. "Pete. Switch to manual. Do it!"

Audio only: "I'm trying, Alpha. Having trouble turning off the computer. It doesn't want to let go!"

Sandra: "Eagle Four on screen."

The main viewer changed its focus to follow the Alphan spaceship's approach. The transport rocked as the automated guidance governing its flight suffered interference, corrupting their descent. Yaw control failed and the nose cone dipped precariously.

Carter looked to both Morrow and the commander and said, "They're in trouble," and then to the viewscreen tracking Eagle Four. "C'mon Pete, switch off that damn computer. Take the stick!"

Kano: "Unable to sever the connection on this end. It's as if the onboard systems have locked up."

Grunts and groans came over the open channel from the flight crew as they struggled to regain control. A feeling of helplessness washed over Main Mission as they watched two of their own struggle to survive.

Professor Bergman put a hand on Koenig's shoulder. "It's a signal, John, hijacking computer guidance."

Koenig leaned forward and slammed his finger on the communicator: "Pete, shut off all data receivers. It's getting into your computer. Shut it out, Pete. Do it before it's too late."

Sandra: "Eagle descent angle ten percent beyond safety limit. Speed increasing."

"Damn it," Carter growled. "Never trust a computer to do a pilot's work. Fly Pete. C'mon, man. Fly!"

The Alphans could do nothing as a battle raged onboard the ship; a battle between a corrupted computer that did not want to relinquish control and the human pilots fighting for their lives.

Koenig repeated his order: "Turn off data receivers, Pete."

"It's overwhelming our systems," Irving's panicked voice relayed. "Everything is sluggish. Flooded!"

The lunar surface rose to meet the wobbling craft.

Paul Morrow slammed an alert button, and a klaxon rang though the base alongside his voice: "Crews to rescue Eagles. Retrieval teams standby. Medical center, prepare to receive casualties."

It was for nothing, they knew. Eagle Four was not simply out of control, but in the grip of computer guidance that had been tainted from outside interference. They weren't going to crash. No, the computer was flying Eagle Four straight into the moon's surface.

As they watched, the spaceship rocked and threatened to deteriorate into a flat spin... but then... but then steadied. The dive flattened; the rocking ceased.

"Alpha..." a loud exhale. "Alpha, Eagle Four here. Control... control regained. Computer locked out."

The reaction in Main Mission was a conflicting chorus of sighs and cheers. Morrow dared a smile as Koenig pat him on the shoulder. Bergman waved a victorious fist. Sandra turned her gaze to the floor and allowed herself to breathe again.

Carter was different. He wasn't relieved but angry; angry that he had almost lost another two comrades. He punched the communications switch and asked, "Can you get her down, Pete?"

"Manual control responding. Yeah, we're good. Landing pad two. I see the beacon."

On the screen, Eagle Four leveled and approached from the horizon, its important payload intact and the ship without damage.

Carter turned to the assembled and glared. "Someone want to tell me why computer almost steered them into the ground?"

Koenig ignored the question and tapped the screen controls. The diamond-shaped intruder, wrapped in a golden aura, returned to view.

Bergman took a deep breath, folded his arms and cradled his chin. "It looks like we have a visitor, John."

"Yes." The commander's eyes narrowed. "An uninvited one."

MARTIN LANDAU

BARBARA BAIN

SPACE 1999

THIS EPISODE... A diamond-shaped golden-glowing object in space... Carter gut punches a security guard... Kano walking on a sandy beach... an Eagle exploding above Moonbase Alpha... squiggly lines flashing on a computer screen... a surgeon in blue scrubs holding up a spinning power drill... THIS EPISODE an Eagle approaching the diamond-shaped object... Carter shouting at the conference table... Kano unconscious in medical... the main Eagle hangar filled with transports... the diamond shaped-object emitting a powerful flash... Kano falling in a black void... a computer panel pulled open revealing an organic brain within.