Smith slumped against the boulder behind him. His mind was numb. They'll be back for me, he told himself, but he knew the situation. Short on fuel and with no machine to refine it with, they wouldn't risk coming back for him. He was… expendable. Still, he was unwilling to accept the fact that he had been abandoned by those he thought of as his family.

He waited and waited, searching the skies relentlessly. Minutes turned into hours. When weariness began to set in, he chided himself,You must keep yourself sharp and aware lest you miss spotting them, Zachary. But as the light faded and the sun of that world sank in the sky, so too did his hope of the Jupiter 2 returning. He hugged himself and suppressed a shiver. Whether it was his mental state or the cool evening breeze that had caused it, he couldn't be sure. One thing was certain, he had to go back to camp. At least he had provisions and the warmth of a fire there.

After quickly searching the former Jupiter 2 camp site for anything usable, he started back to his camp. His mental dialogue continued. Who are you kidding, Zachary? You were a menace. They couldn't wait to get rid of you. They took Kai because, unlike you, he was useful and cooperative. No, strike that. He fooled them into thinking he was useful and cooperative. And if it wasn't an accident that hurt Penny… it HAD to have been Kai. That manipulative monstrosity is to blame for all of this, though you certainly made it easy for him. Smith sighed heavily. Be that as it may, you're stuck here… alone.

As he arrived back at his camp, he bent down to scoop up his jacket. He shrugged it on and zipped it up. He chucked a few logs into the circle of stones that served as his fire pit and lit it with his laser pistol.

The rumbling of Smith's stomach reminded him that he hadn't eaten much and he was short on food. He needed to gather more wood for the fire. He debated a moment what he should do first, but he realized if he sat down to eat, he'd never gather the firewood. As hungry as he was, he'd rather be warm. So, he grabbed a pack, to make carrying the wood easier, and set off towards the river where he knew there was some driftwood.

As he neared a grove of trees, the stench of rotting flesh assaulted his nostrils. He searched cautiously for the source of the smell. Rotting flesh would attract scavengers, or worse, and he certainly wished to avoid that. He rounded a rock and found the corpse of an animal whose appearance was reminiscent of a large Earth cat, only much larger. It had overgrown canine teeth, like that of Earth's sabertooth cats, but smaller. It also boasted a long tail, at least three quarters the length of its body. Though he'd only had a quick glimpse that dark night, Smith recognized it as the predator that had stalked him near his camp.

Large sections of the creature's flesh had been removed so precisely, it looked almost surgical. Smith swallowed to keep down the bile he felt rising in his throat. As a doctor, he was no stranger to blood and gore, but what had been done to this once magnificent creature horrified him. It suddenly occurred to him that the creature had most likely died due to the wounds inflicted by his laser pistol. Then Kai had probably harvested its meat for food shortly before liftoff. That fact both relieved and frightened him. He was relieved the alien was gone, but despite trying to convince himself that he didn't care, he was afraid for the Robinsons. He may have been angry at their abandonment of him, but he couldn't bring himself to wish them dead, especially in such a dreadful manner.

He didn't dare stay in the area any longer. As he turned to find firewood, he heard a small sound of distress. He shrugged it off and took a few more steps, but he heard the sound again and stopped. Curiosity got the better of him and he turned and went back.

Near the large cat's head, which rested near a rocky crevice, he found a pair of small bodies, cubs who had recently been born. He knelt down and touched them, feeling for warmth, looking for signs of life, but they were as deceased as their mother. As he stood, he heard the sound again and this time was sure of its location. Gently, he reached into the crevice. He felt his hand touch something warm and wet. He grasped it and pulled it out. It was a small cub, not much bigger than his hand. Its mother hadn't even had the chance to clean it before she died.

The cub, who had made a sound just moments earlier, didn't move, despite Smith's prodding. He could feel a faint heart beat, but then he realized the little animal wasn't breathing. He cleaned the creature's face with a handkerchief he pulled from his pocket, then covered the nose and mouth with his mouth, delivering a small puff of air in hopes of jump-starting its breathing. He pulled back and checked, then delivered another small puff. He was rewarded with a tiny cough and a cry as the cub stirred to life. Smith dampened his kerchief in the nearby river and proceeded to clean the creature as best he could.

As near as he could tell, the cub was female and the runt of the litter. He held her in the palm of one hand and stroked her ebony fur with the other, while studying her tiny face. The small tuft of white fur under her chin stood out against the rest of her jet black coat. He noticed that, unlike Earth cats who were born blind and deaf, this cub's eyes were open and she certainly seemed to respond to the sound of his voice. The observation both fascinated him and bothered him. If evolution on this planet had seen fit to make that little creature so aware of its surroundings at birth, there must be something dangerous enough to warrant such a trait. The restless movement of the little waif resting in his palm brought his thoughts back to the present situation.

Smith didn't particularly want the added responsibility of caring for the creature, but he couldn't bring himself to simply abandon the helpless thing, as he himself had been abandoned. Besides, he felt responsible for the death of her mother and he needed companionship, any companionship. Since his options were limited, this little creature qualified.

"Well, little one," he said, "it seems, for better or worse, we're in this together." She mewed, seemingly in agreement. He scratched beneath her chin with an index finger, which she promptly grasped with her mouth and began to suckle. Smith smiled. "Hungry, are we? I'm not sure how I'm going to feed myself, let alone you, but we'll figure something out. We'll have to."

Hugging her to his chest, he set off in search of firewood. The cub mewed insistently, begging for food. Smith talked softly to her, promising she'd be fed when they arrived back at camp. Her little claws dug into Smith's jacket as she tried to pull herself closer to the source of his voice. Smith could only smile at her tenacity. She was a survivor… like him.

Back at camp, he dropped the pack full of firewood. Still clutching the little cat to his chest, he sat on one of the rocks, and gently placed the cub in his lap. He rummaged around in one of the packs and withdrew his canteen, the first aid kit, and a small canister. Inside the canister was powdered milk Mrs. Robinson had left for him, to which he added some water and mixed well with a small eye dropper he'd retrieved from the first aid kit. When it was well combined, he filled the dropper, picked up the cub, and put the dropper near the cub's lips. She sniffed and her tiny tongue licked experimentally. Quickly, she latched on to the end of the dropper and began to suck greedily. Smith squeezed the dropper's bulb gently, delivering more milk to her. When she had drained the dropper, he refilled it, and continued to feed her until she was satisfied.

Smith threw some more logs on the fire and heated some morsels of food the Robinsons had left him. The cub curled up at Smith's feet and snoozed in the warmth of the fire. Despite his overwhelming hunger, Smith forced himself to ration the food he had until he could find a stable native source.

When his meager meal was finished, he packed everything away again, checked his bed for unwanted guests of the creepy, crawly, and poisonous variety, crawled into his bed, and got comfortable. He laid down on his back and placed the cub on his chest, one hand resting atop her to keep her from wandering off. The cub, satiated from her feeding, and Smith, exhausted from the traumatic events of the day, both dozed off quickly.

After a quiet dinner with the rest of his family, Will lay wide awake on his bunk, only able to think of his friend, Doctor Smith, all alone. Any one of them would have a hard time surviving the wilds of an alien world, but Smith least of all. While he was thinking, it suddenly occurred to him that their hasty departure had distracted him from his investigation of the Robot's odd behavior. Curiosity getting the better of him, and needing something to distract himself, Will hopped up off his bunk and went to find the Robot.

Not only did Will find the Robot. He found Kai as well.

"What are you doing to the Robot?" Will asked.

The alien was startled. He expected the humans to all have fallen asleep by now, especially the young ones.

"I was making some adjustments," Kai replied.

Will spied the small programming unit Kai had tried to hide in his hand. "To what system?"

"I was hoping he could help us with navigation. Since fuel is short, we need the shortest, quickest route to my planet."

He studied Kai. What the alien said made sense, but Will didn't believe him. "Maybe I can help you," the boy offered.

"I think you should be getting to bed."

Will hesitated for a moment, then agreed. "Yeah," he faked a yawn, "I am kinda tired." He went back to his cabin and closed the door, leaving a small crack with which to spy on the alien.

Kai resumed working on the Robot, irritated at the interruption. It wasn't long now until he could rid himself of the pesky humans and take the ship back to his home world. Perhaps tonight, if the opportunity presented itself.

Will watched Kai through the crack of the door. He became alarmed when he saw his sister Penny leave her room and approach the alien.

"Hello, Kai. What are you doing up so late?" she said as she strolled to the galley for a glass of water.

"Working on the Robot," he said with a tinge of annoyance.

"What are you doing?" she inquired as she filled her glass. Her thoughts mirrored her brother's, though she had not formed any suspicions as he had. "I hope you're fixing whatever problems he's had lately."

"Problems?" Kai looked up from his work on the Robot and stared blankly at Penny. "What problems?"

Penny walked over and stood by the Robot, resting her hand on top of the smooth metal that served as the Robot's torso. Will held his breath, hoping his sister would figure out the danger she was in and extract herself gracefully before Kai did something rash.

"Well, just, there's something very different about him lately. Did you change any of his programming?" Penny peered at the front of the Robot. Not thinking, she reached over to slide back the access panel to the Robot's programming tapes and started to peer in. Instinctively, Kai grabbed her wrist and forced her back. He was quickly tiring of these humans.

Penny tried to squirm away. "Kai, you're hurting me." But the alien held tight.

Will fought the urge to rush out and help his sister. He'd be no match for the sizable alien. He searched his cabin for something to use as a weapon.

Kai wrestled with the girl. She was remarkably strong for a young human, but he managed to quickly get a hand over her mouth and held her securely against the wall. Penny struggled for a few more seconds and then slid slowly to the floor. It all happened so quickly. The only reason she knew she'd been bitten is because she had seen the flash of fangs and was quickly succumbing to whatever they had injected.

Seeing his sister slump to the floor threw Will into a rage. He charged Kai, swinging one of the metal legs he had unscrewed from the table in his cabin. He connected a few times, causing minimal damage to the alien's armored hide. Kai grabbed the weapon and tossed it aside. Judy and Mrs. Robinson, drawn to the commotion, came out just in time to see Kai catch Will's flying fists. He squeezed them until the boy cried out in pain and then backhanded him, knocking him unconscious.

Mrs. Robinson cautioned Judy and motioned her to move to Kai's other side, splitting his attention. She grabbed a knife from the galley and tossed Judy a meat tenderizing mallet. "John!? John!"

The Professor heard the cries from the upper deck. He glanced at the Major and the Major nodded back. The Professor bolted to the ladder and dropped down to the lower deck while the Major went to grab a laser pistol.

As the Professor turned, he saw his wife and daughter struggling with Kai. Mrs. Robinson had plunged the knife into the alien's shoulder and was hanging on tightly to it, despite the fact that Kai had a firm grip on her throat. Judy had climbed onto Kai's back and was pummeling his thick skull with the meat mallet. Before the Professor could get to them, Mrs. Robinson fell to the floor and Kai slammed his back against the wall, knocking the wind out of Judy.

Kai pulled the knife from his shoulder and flung it at the Professor, who ducked and then lunged, shoving his shoulder into Kai's mid-section. Kai grabbed him in a wrestling hold and the two struggled across the deck. Major West landed on the lower deck, pistol in hand, and held it up, looking for a clear shot at the alien. The Professor saw him and tried to muscle Kai into a good position. The Major fired, but it did little but singe the clothing and thick natural armor of their enemy.

"Don! Get the others to safety!" the Professor commanded.

The Major kept up occasional laser fire as he dragged each of the Robinsons across the deck into one of the cabins. Then he went back to help the Professor.

The Professor was pushing against Kai's chest and throat, keeping the alien's vicious striking fangs out of reach. The Major holstered his weapon and rushed up behind the alien, locking his arms around his waist and doing his best to pull him away from the Professor.

"Freezing tube," the Professor gasped, exhausted from the fight. Immediately, the two worked together to maneuver Kai onto the elevator. The alien's claws sliced the Professor's forearm and he grunted in pain. The Major slammed his left fist into Kai's chin, dazing him for a second. The Professor followed with a right uppercut. As the elevator reached the upper deck, both men timed their punches to connect at the same time, slamming the alien's head against the wall.

"Quick, before he recovers," the Professor ordered. They strained and grunted as they tried to force the mountainous creature over to the closest tube. Kai lashed out and his claw struck the Major's thigh. West fell to the ground clutching at the wound. The Professor managed to hit a button on the side of the tube while Kai was preoccupied with the Major. As Kai pounced on the wounded man, he received a swift kick to his gut from his downed opponent's good leg and stumbled backwards into the astrogator. The Professor raced across the deck towards the air lock. Kai quickly followed.

As Kai caught Professor Robinson, the human turned and slammed the metal fire extinguisher into the alien's jaw. Kai flew backwards into a console, which erupted into sparks and smoke. The Professor went on the offensive, swinging the canister at Kai again, but the alien rolled out of the way. The extinguisher further crushed the console and the ship lurched and shook violently. The combatants crashed to the floor, unable to keep their feet as the ship flew out of control.

The Professor slid across the deck toward the freezing tubes, followed by the hulking alien. Grabbing the tube, the human hauled himself to his feet, while Kai used the astrogator to get to his. As soon as he was upright, he charged at the Professor, who deftly dodged, like a matador sidestepping an angry bull. Before the alien could turn around and escape, the Professor slammed his hand against the button that closed the tube and froze their enemy solid.

The ship lurched again and the Professor hit the deck hard. He slid across the deck next to the Major who was hanging on desperately to the astrogator. "You ok?" he inquired.

"I'm ok," the Major replied. "Get me to the chair and I'll get the ship back under control."

The Professor obliged, helping his friend limp across the constantly shifting deck to the flight chairs.

"Go check on the others," the Major told him.

The Professor looked at the damage to the Major's leg as he got strapped in to the chair. "That's gonna need stitches." The Major nodded at the Professor's forearm, "So's that."

By the time the Professor got to the lower deck, Mrs. Robinson and Will had regained consciousness. Judy was tending to Penny and they were all looking worriedly at her. They sat on the floor. It was easier that way with the ship still lurching back and forth.

"What happened?" the Professor asked as he kneeled next to Penny, but when he saw the two puncture wounds on his daughter's neck, he knew. "Is she ok?"

"She's stable," Mrs. Robinson replied. "I… I don't know how she'll react to his venom."

"Dad? What did you do to Kai?" Will asked.

"Is Don ok?" Judy added. Her hand instinctively moved to her father's forearm when she saw the bleeding gash.

The Professor's concern for his family and a good shot of adrenaline had blocked out the pain, but once things calmed down, he began to hurt. He grabbed his forearm and applied pressure. "Kai is in one of the freezing tubes. He won't be a problem any more. Don and I both were slashed. We'll probably both need stitches, but we'll be ok."

"Dad?"

"Yes, Will?"

Will voiced the suspicions he'd been harboring ever since he realized the Robot wasn't right. "I don't think Doctor Smith sabotaged the deutronium refiner. I think Kai did it and re-programmed the Robot to frame him. Penny and I discovered him tampering with the Robot again tonight."

"I think you're right." The Professor agreed. He grasped Penny's hand and prayed a silent prayer that Kai's bite wasn't fatal.

The Major's voice came over the comm system. "You all had better strap yourselves in. We're going to have to land… and quick."

The Professor ushered his family out of the cabin and each got strapped into a flight couch, with the exception of Penny. The Professor carried her still unconscious form to one of the couches and strapped her in himself. Then, he strapped himself into a couch next to his wife. Grasping her hand, he mouthed "I love you".

The ship pitched violently as it plunged into the atmosphere of a nearby planet. Major West fought the controls, trying desperately to flatten their trajectory so they'd have a chance. The Jupiter shuddered, but ultimately obeyed, slowly straightening out. Some of the retro rockets refused to obey, slowing the Jupiter to only half as much as they needed. The Major guided the ship toward what appeared to be a vast prairie.

"C'mon, baby," he coaxed. Mentally, he counted down as the ground rushed up. Impact threw him back and forth like a rag doll. The saucer bounced like a frisbee skipped off of concrete. It thudded into the ground again, this time staying in contact, slowing to a stop, and then, thankfully, settling horizontally.

"Everyone ok down there?"

The Professor picked up the microphone near his couch and replied "We're all ok down here. Good job, Don."

The Professor, Judy, and Will went topside to survey the planet they'd crashed on. Mrs. Robinson stayed with Penny to monitor her condition.

Four of them stood in front of the viewport, looking out onto the vast yellow expanse before them. "Get used to it, folks," the Major said. "It might be home for a while."

It didn't have to be said, but the others understood that "a while" might mean "permanently".