A/N: Wow, guys. I can't believe this is the end. Enjoy.

Epilogue

Ellie stood outside the observation room, darkened glass shielding her from Isaac, separating her from the man she loved. For three months, she'd wanted badly to go to his side, but the doctors had warned her against it. 'Psychologically fragile' were their exact words. They wouldn't tell her why, even after she threatened them with Samson and when that didn't work, with the Captain. It hadn't made a difference. They told her no, with such a kind firmness that she obeyed but thoroughly resented.

From where she lingered, she could see the rise and fall of his chest, the numbers the monitors spat out on holographic screens. Everything healthy and mended and functional. He should be with her. He should be awake and laughing and at night he should be in bed beside her, their conversation carried across the pillows in hushed whispers. He should be working with her to find the origin of the Markers to end this fight once and for all.

"His guardian angel makes an appearance. Figured you'd be here." Trey had come up from behind and stood with her at the window. His smile was an easy one that reached his blue eyes. "He seems to be resting well."

Trey was making conversation, but she didn't want small talk. "I'm tempted to break him out of there. I hate they won't let me get any closer."

"Ellie," he squeezed her arm, "I think they know you're on the warpath to find the Marker's source signal. They don't want you probing Isaac for information."

He was right, and she hated it. "He's the best chance we have."

She allowed Trey to tug her from the partition into a walk. They strolled through the hospital deck in amicable silence and both seemed to appreciate the buzz of human life around them. Ever since the Grey Marker, she'd been feeling focused. Honed. Empowered. She hadn't wanted Isaac to throw himself into the mechanisms of Unitology, but from her experiences on Rhea, she understood the importance of putting an end to the Marker signal. Isaac was the one person standing between the spread of the Necromorph plague and human beings. She didn't want him to stand alone anymore.

"So I heard something interesting through the grapevine earlier," Trey said. He hit the call button for the elevator. "About you and Norton."

"Oh?" Probably had something to do with those long hours they'd been spent together to discuss EarthGov's movements. She waited for Trey to drop the shoe.

"Yeah." Together, they stepped into the elevator. Trey tapped the number for the lobby. "With all the time you two've spent together, some tongues are wagging about the, er, intimacy of your relationship?"

"Norton's the contact in EarthGov. He's important to our mission, so of course I'd be working with him as much as possible."

"Look, as a friend, I support you. But Isaac's going to get better soon and everything he's done, he's done for you. He may not see the relationship solely as 'working'."

"Are you saying I've been unfaithful?" Trey's suggestion, the implication that she would betray Isaac, stung her. She shifted to face him fully and tried to keep her tone calm. "I can't help what other people think. I can't help that I every time I visit Isaac, I can't actually speak to him. So when Isaac's better, things between us will be as fine as they ever were."

"I know that. I'm making sure you did," Trey replied. "You and Isaac are together in this. Both of you are better with the other than without."

Later, she wished she could believe that Trey had spoken the truth.

Another month was up before Isaac was deemed fit enough to leave the hospital. Ellie waited for him in the lobby of the Med Deck, her stomach in knots, eyes fixated on the elevator doors. She was giddy, schoolgirl-ish, as she waited in a cushioned seat. She was there alone, as the doctors told her to minimize the excitement, and when he got home, to ensure he got plenty of rest.

She endured what felt like several hours before the elevators sighed open. Two nurses flanked him, but he was on his feet, wearing normal clothes- -plain grey shirt, dark jacket, jeans. His stay in the hospital had thinned him out, bearded him, and although he'd had salt-and-pepper hair, she noticed more salt there than before. It didn't matter to her. She surged forward and was careful not to fling herself too hard into his arms. The hug nearly killed her with its relief and happiness, and when her eyes stung, she let the tears flow.

"It's good to see you," he murmured. His stubble bristled along her forehead when he planted a kiss there. "I missed you."

Dear God, she couldn't control the emotion. Her throat had thickened, so she nodded into his shoulder instead of speaking. He smelled all wrong to her, like laundry soap and hospital antiseptic instead of the grease and spicy aftershave she was used to. And she was aware of a hunger inside her, for his sea-green eyes, for a smile that crinkled his cheeks, for his callused hands to caress her, for him.

They embraced awhile until the uncomfortable presence of the nurses drew them apart. She was familiar with the male one, Logan. He had brought her coffee and granola on the long nights after they'd pulled Isaac's broken body from the wreckage and everything was touch and go. Isaac stood back, and it seemed he allowed her to take control.

"Ellie," Logan said, showing her a datapad, "the scripts have been sent to the pharmacy. You'll need to stop at that counter before heading home. The directions are self-explanatory, but if you have questions, contact us. It's vital all meds are taken on schedule. Also, you'll be hearing from a psychologist, Dr. Cross. She's great at what she does for the ship." Logan smiled and offered his hand to Isaac, who shook it. "Good see you on your feet, Mr. Clarke. Ellie, take care."

Isaac nodded as Ellie responded, "Thank you for everything. Thank you."

Logan and the other nurse parted, and Ellie and Isaac walked to the pharmacy counter for his meds. Afterwards, Ellie tucked her arm inside his and they began the route to their living quarters. He seemed pensive to her, quietly taking in the sights, and she let the silence pad them. People had gotten used to him at this point and so they left him alone, much to Ellie's relief. She had worried that everyone would flood him to wish him well, and she'd have to be the bad guy in telling them to sod off.

"Talk to me," Isaac said when they had the tram to themselves. "What'd I miss? Those doctors wouldn't tell me anything."

Ellie chuckled and scooted closer. He slung an arm over her shoulders as they sat on the hard bench. "Where to begin? Ah, well, Trey, Leo, and Calhoune are fine. Their injuries weren't as severe as yours were. Those three have been my main team on off-ship missions. The Major didn't make it, but the girl he was with…Ivy? She's working with Samson to uncover the true purpose of Oracle. Noah and Lexine were recovered in stasis pods, and I think that Noah's got a crush on Lexine. He won't leave her side." She glanced at Isaac and saw the corner of his mouth wing up. "She's due to give birth soon, so that's the buzz. Oh! And Sher and Cookie were rescued by EarthGov agents. Last I heard, they were trying to connect with their families."

"That's a lot that's been going on," he said. "What about these off-ship missions? What do those involve?"

She grimaced. "You've just got on your feet. The doctors want you to have plenty of rest." Her evasion satisfied him.

The next few days were quiet. Isaac kept to himself. He was never an outgoing person, and he was content to sit at the desk facing the window and sketch- -he used a datapad and stylus to create files and files of sketches. He didn't hide what he drew from her; it was Marker cuneiform and Marker designs. Wary of spiraling depression, she tried to urge him to the mod shop, and Samson even tried convincing him to help in Engineering, but he shook his head. He read a lot, took his meds, politely refused invitations to gatherings or meetings, and didn't return Dr. Cross's pages.

Finally, Ellie'd had enough. "Isaac, you've got to start getting out. This brooding isn't good for you."

"No," he told her. "I don't want my head picked apart. And I don't want to be looked at like I'm a freak."

"No one thinks you're a freak." They were at the small, two-person island inside the kitchenette. Coffee steamed from mugs, forgotten, between them. "Samson needs your help with the suits and weapons. He and Ivy are still sorting out the Oracle files. And I'm going with Norton to meet a contact, someone who has access to Marker research that could tell us the location of the source. Please, this is important."

He let her words hang in the air. Then he raked a hand through his short hair. "Ellie, I'm leaving Retribution."

It took her a pregnant pause to process his words. "What?" In her chest, her heart twisted.

"I don't want to be involved anymore. I'm exhausted. I just want peace." His tone had dropped to a soothing murmur. "You're fixated on finding the Marker's source. How do you know it even exists? And then there's Unitology and EarthGov. Both of which want me dead. What does it even matter? Even if the source exists and we somehow miraculously destroy it, some new improved death threat will take its place."

His sudden pacifistic view aggravated her. "Isaac! There is no one else better equipped to deal with the Marker's threat. Don't you care that billions of innocent people might be wiped out? I'd say that matters quite a lot."

"Don't take this path," he said, leaning forward to fold her wrists in his hands, "because I can't walk with you. I'm done. I can't give more than I have already. It's not in me. I'm empty."

"It was you who wanted to destroy the Markers in the first place! You had to convince me it was a good idea, that it was your fucking duty to do what you could do. And now that I'm finally on your side, you've fallen back?" The words got stuck in her throat. Betrayal cut her deeply, but she controlled the hurt, controlled the anger that rose a hot tide inside her. "I don't understand. It was you who told us about the source. That destroying it would dismantle the Markers permanently. Why are you backing off?"

"Jesus, Ellie, you sound like some goddamn fanatic!"

She flinched from his accusation. He sighed, his shoulders sloping as if under a heavy burden. His eyes crinkled in a mask of pain, pain that she caused with her feelings and words, and that pain forced her to calm. He'd been through so much alone, he was used to being solitary and not sharing his anxieties and agonies. She had to be gentler- -impossible considering she plowed through problems until they were solved.

"Look," sorrow shaded his voice, "I could never live with myself if you were to get hurt or killed because you're chasing some stupid, crack-pot theory that I started. Maybe it's a ploy to trap more people. We don't know. Please, can you let this go? Let Samson and the Clarke Faction worry about it. Let's leave the ship and live."

He'd brought their conversation back around full-circle. Before she could respond, the door buzzed. Shit. "That's Trey. I have to go, Isaac." She stood, a confusion swirling inside her because she loved this man, she wanted to fight and she wanted him fighting beside her, not with her. They kissed goodbye- -a hurtful kiss since nothing had been resolved, and she opened the door to Trey.

He held his gaze on her as they walked to the tram station. "Everything okay?"

"Yes."

"No, don't do that," he said and took her arm. She shook him off, not wanting to discuss it. "Something is going on between you and Isaac."

"It's none of your business," she snapped. Honestly, where did he get off on prying? He grimaced and in strained silence, they went to the docking bay where the Eudora was clamped for supplies. Norton was on a catwalk as his crew loaded up the ship, his soldier's shoulders and broad nose residing over his small piece of the universe with firm command.

Ellie and Trey waved at him from the deck. Norton's scowl lightened and he climbed down the ladder to where they stood. He greeted Ellie with a smile the same time he shook Trey's hand.

"Agent Langford." A gentle tease was present in the tilt of his head. "Pvt. Treyton. We're almost geared up. Not too long now. You ready?" His smile was a pleasant one, and she relaxed in his strong and controlled presence.

"We're good," Trey responded. Ellie caught his quick glance in her peripherals.

"Treyton, report to the armory to secure your gear. I'll brief Ellie on the specifics of our mission," said Norton.

Trey hesitated, again glancing at Ellie, but saluted. "Yes, sir." He went up the ramp into the Eudora's belly.

Norton had a datapad in his hand. He showed it to Ellie, queuing up a picture of a pretty woman with dark hair and eyes and elegant features. She was Damara Carver, an EarthGov Data Archeologist who had access to Marker research records.

"Her husband is John Carver. He was under my command but got demoted and sent off to some shithole in the Outer Rim." Norton spoke, his voice deep and coaxing, and tingles spread along her spine. "He's the reason I know her."

He continued with the minutiae of the mission. With his arm and shoulder pressed to hers, a flash of sensuous heat burst through her that was a total surprise. When had she and Isaac last had sex? She couldn't remember and regretted that they'd spent their morning arguing. But he hadn't been emotionally present the last week except to deflect her conversation regarding the Markers.

"Ellie? Am I boring you with the details?" There was that tease. The humor came so easily to him. "I'd hate to take you on a date with that attention deficit you got going."

"Is that an offer? Because, you know, I already have someone." She paired the refusal with a smile. "But consider me flattered."

"He must know he's missing out." With that comment, Norton shrugged and continued briefing her on the contact.

On the flight to the contact point, Ellie had plenty of time to ruminate. Isaac had a valid point. He did seem worn thin, a shell of a person. He needed time to recoup where no one could pressure him, where she couldn't pressure him. Maybe if this mission went well, she could relax her duties and she and Isaac could heal together. If Damara Carver came into the fold, she would be responsible for transmitting the Marker's code to the Clarke Faction. Ellie had no control over how quickly or how much Damara could translate; Ellie would have to wait like everyone else for Damara to do her work. She would have time for Isaac.

Everything would be fine.

At the meeting, Damara Carver understood the dire situation without disbelief. When Ellie expounded the importance of what the Clarke Faction did, Damara showed Ellie a holo-image of her son. He was a beautiful little boy, with dark eyes like his mum, smiling with child's innocence at the image-taker. Quietly, the two women agreed to protect the future of civilization or die trying.

"She's a very strong woman," Norton said as they watched her shuttle lift off. "She'll do us proud."

Ellie nodded. "She's our best lead to the Marker's source."

"Captain! Captain, we've got a problem." Austin, their communications officer, broke through some static on Norton's RIG. "An EarthGov Yellowjacket got clearance from ATC to uplink to the ship directory."

Colonies used satellites to scan and register incoming ships. Each ship had a signal that automatically broadcasted the ship's registration code which was then stored in the ship directory. It was possible to disable the signal broadcast, but if done incorrectly, could permanently cripple the ship. Much easier for bandits, magpies, and smugglers to purchase a cloaking program.

"Shit. They see the Eudora's registration number on that directory, they'll know we're here and not on patrol in our assigned sector," Norton said. "Okay, Ellie and I aren't far. Keep our signal cloaked, but if you need to scram, do it. You can pick us up when the coast is clear."

"Roger that, Captain."

Norton grabbed Ellie's wrist. She ran with him out of the abandoned colony foodcourt to the old-style Jeep they'd parked outside. Ellie had never seen a car except for in museums, but Norton had outfitted it with a plasma drive and had laughed when she'd been dubious about riding in it. Then she'd sat in the passenger seat, and she'd felt a wild sense of romanticism as he drove her to the contact point. That excitement faded, though, when Norton threw the Jeep in gear and punched the accelerator.

The ride was rough- -her teeth clattered and she gripped the door- - the tires slid when Norton swung around the tight corners, flinging gravel and silt in waves over trash and debris. A long strip of barren ground spread in front of them, dilapidated housing complexes crowding beside the road. Norton gunned the Jeep. Ellie felt the acceleration, the wind whipping her hair and roaring in her ears.

Norton's audio switched on. "Captain, EarthGov's issued a planet-wide alert for the Eudora."

"We're half a click from rendezvous," Norton said. His hands tightened on the wheel. "Keep the engines idling and prep for a hot lift-off."

"Yes, sir."

Ellie watched the landscape blur past, grey and blackened structures running together, and under the Jeep's hum, she heard a high-pitched whine. Then between the buildings, she caught the flash of yellow enamel.

"Norton! EarthGov, three o'clock!"

Norton cursed. "Keep eyes on it, Ellie."

The Yellowjacket was a sleek craft built for tracking and apprehending criminals with extreme prejudice. Ellie had seen Yellowjackets in action- -they were compact and fast, operated by hardened militia, and equipped with enough firepower to level a city block. She tracked the Yellowjacket as it swerved into view overhead and behind them. It was close enough that she caught the eyes of the co-pilot.

"This is the EarthGov Military Intelligence Force. Captain Robert Norton, you are ordered to stop the vehicle and surrender. Repeat, you are ordered to stop the vehicle and surrender," said the co-pilot over the Yellowjacket's loudspeakers. "If you do not, we are authorized to use deadly force."

"I guess I'm an outlaw now," murmured Norton. He squinted at the dirt track in front of them. "Ellie, behind the seat is a grenade launcher. Use it to lock-on to the y-j and bring it down. I'm taking evasive maneuvers."

He careened the Jeep to the right. Ellie was flung against the door, but gamely reached back. Her fingers brushed a hard case, came into contact with a handle. When she tugged the handle, the case snagged and she couldn't free it. Norton zigzagged between the buildings, but the Yellowjacket kept pace. A second later, an explosion rocked the Jeep, showering Norton and Ellie with stones and debris. In the chaos, Ellie twisted in her seat, kept a hand planted on the dash for support, and threw herself into the backseat. Her head whammed into the door, dazing her, but she bit down the blare of pain.

Missiles whistled and blasted around them. Norton kept the Jeep speeding ahead of the Yellowjacket, but the pilot was good and kept on their asses. Ellie knelt in the backseat, a haze of red clouding her vision, and fought to open the case. She worked free the latches, the case popped open, and a black weapon lay on foam, with a ring of ammunition. In practice moves, even against the sharp sways of the Jeep, she prepped the launcher and ammo, and hoisted it into her shoulder.

She had the Yellowjacket in her sights even at it swooped and dipped side to side. The small flip-screen showed green- -target locked. She squeezed the trigger as Norton fishtailed around another corner. The grenade flared an arch in the sky, spiraled, and hit the Yellowjacket's nose. Bright flames plumed across the craft. It dropped and peeled off to the side, missing a building's corner by centimeters. She heard the crunch as metal met ground. That was the break they needed. Norton wove through the deserted area to where the Eudora had the ramp open and screeched to a stop in the hold.

"Get us out of here!" Norton told the co-pilot. The ramp snapped up behind them, and in a daze, Ellie accepted Norton's help in exiting the Jeep. "And send a goddamned medic down here. Ellie's bleeding."

Her injury was a minor cut on her brow, but as the medic put the analgesic on, Trey swooped in, his brow clouded in worry and anger. He checked over her, made sure she was as fine as she said she was, and helpless, Ellie watched him take Norton behind a door. Some raised voices filtered through the ducts. After the medic stuck a bandage over the wound, she saw them exit. Both men had deep scowls.

Her immediate assumption was they had argued over her; Trey had stuck to her like glue after Rhea station, and though he wouldn't explain his careful guardianship, she expected Isaac had something to do with it. Prior to meeting with Damara, Ellie had to convince Trey that she could take care of herself. Nothing would happen, she'd told him. She didn't need a protector. What they did was dangerous and the last thing she wanted was someone stressing over her, either up close as Trey did or from afar.

She sought out Trey and found him in the armory, cleaning guns with strict concentration. He glanced up when she came through the doors, frowned, and returned to the pieces in his hands.

"Trey, we need to talk." Ellie sat across from him. The smell of grease and cleaning solution was pungent. He didn't respond, so she touched his forearm. "Hey."

He slapped the parts to the table and addressed her directly. "What you did was reckless and you could've gotten hurt much worse than you did. I should've gone with you or you should've stayed on the ship."

"That's well and good, but you can't stop me from doing what I think is right," she said. "Short of throwing me in the brig, I'm going to take risks because that's what we have to do. I don't need you to…trade your life in for mine."

"I made a promise to watch your back." His gaze drilled into her. "I don't break my word."

"Was it Isaac? Did Isaac make you promise to watch over me?"

He shook his head. "I can't tell you."

"You mean you won't." Not that she needed him to say it. Isaac's fingerprints were all over this. She made a disgusted sound at the back of her throat. "I can take care of myself. I have since I was eight. Trey, you have no obligation to me, no responsibility. Isaac had no right to ask that promise of you. And I want you to stop it."

"It wasn't-"

She cut him off with a quick gesture. "Please, I'm not stupid. There is one person in this cosmos that has that type of persuasion and reason. Trey, look. I'm going to get bumps and bruises. I may even die. But it will be a worthy sacrifice to stop mankind's extinction. You know that as well as I. Stop worrying about me and start worrying about the Marker's threat."

Trey drooped, his shoulders hunched. "Isaac's gonna kill me."

"You let me worry about Isaac," she told him. They regressed into silence; Trey fooled with a coil in front of him. "Out of curiosity, what exactly did you say to Norton?"

"Things I shouldn't have to a commanding officer." He chuckled. "Man, my ass is toast."

The tension between Trey and Norton was short-lived. The Eudora was not pursued, and within the week, they docked on Retribution. To her surprise, Samson met her on the flight deck. He seemed harried, pale with concern.

"Ellie, I'm so sorry," he began, and a pit grew in her stomach. "Isaac's left Retribution."

She had nothing to say. Coldness and grief swelled inside her, closing off her lungs so she couldn't breathe. No. Now's not the time to be weak. Still, her knees were watery and a horrible sense of betrayal seared across her heart. Why had he left without her? Why? So many questions burned her, and no answers to soothe it. Dazed, she allowed Samson to guide her into a private cubicle.

"Where did he go?"

Samson touched her shoulder. "We don't know. He disappeared forty-eight hours ago. We speculate he stowed away on a shuttle and deactivated his RIG. We can't reach him and can't track him. But he did leave something behind." He handed her a chip. To her unasked question, he said, "It was addressed to you. We didn't watch it."

Ellie slotted the chip into her RIG, and then choose the public-play option. The shot was of Isaac's head and shoulders. Dark half-moons shadowed under his eyes. Instantly she knew he hadn't been sleeping- -and that was because he'd stopped his medication.

"Ellie," he said. He rubbed his temple with a couple fingers. "I couldn't wait. I needed to get from under the pressure, to start somewhere no one knows who I am. If I'd waited, we would argue, and somehow we'd both end up hurt. The point is, we're doing what we feel is right. You're throwing yourself at the Marker, and I can't watch you die. Besides, there's…there's something wrong with me," his eyes shifted and his look darkened, "something the Marker caused that's different from the dementia. It might hurt you…I don't know and I can't risk it.

"I just…want you to be free of me, of the Markers. Please, go be free." His sigh was heavy, burdensome. "Anyway, I deactivated my RIG, but if you need me, here are my coordinates." Her RIG bleeped with a file download. "I hope to God that whatever you do, you're careful. Give my regards to Samson. And please, keep where I am secret. I don't want anyone following me."

Then he signed off. No goodbye, no I love you. Ellie stood in the silence, staring at a section of the wall, and tried to get a handle on what she felt. Anger. Hurt. Sorrow. An emotional whirlpool that threatened to drag her underneath. Most of all, she wanted to confront Isaac, to tell him what a coward he was for running away. But that's what he expected to happen. He expected an argument, to say things that would cut and distance them further. That's what he wanted: distance from her. She set aside her anger, her regret, as hot as it was, and inhaled a cleansing breath. Isaac wanted to be left alone, but she couldn't leave everything like this, like a mess.

"Samson, can you get me a shuttle?" Ellie turned to the old man. "I have to see Isaac."

"I'm afraid he won't come back," Samson told her gently. The truth of that was absolute. She knew she could try to force their relationship, but Isaac had made it perfectly clear that he wasn't hunting Markers, not now, not ever. She could not rely on him for help any longer.

She nodded. "I know. But I love him enough to give it another try, and if that doesn't work, then to make a clean break of things."

"I see."

Samson coordinated a single-pilot shuttle for her. As she waited for clearance, she traced the raised outline of the St. Christopher's necklace Isaac had given her. She kissed the cool metal and thought about the story behind the symbol- -a man carrying the weight of Christ on his back. It hadn't broken Christopher, but then again, Isaac had carried a different weight…the weight of humanity. He'd even sacrificed his sanity for it. Perhaps he'd carried it far enough and needed her to carry it because he no longer could.

Maybe, in time, he would pick up the burden once again. She didn't know. What she did know was that she would sacrifice anything to prevent the human race's extinction. And if she had to carry on without Isaac…then she would carry on. It would carve out her heart to leave him, but that would be her small sacrifice in the face of imminent danger.

A/N: That's it, folks! I took a liberty with using Ellie's voice and a lot of time-skip transitions, so I apologize if it feels disjointed. Thank you to everyone who followed & favorited & reviewed the story. You hung in there with me and I appreciate it enormously. I'm amazed that so much time has passed and that I've actually finished the story. It's a huge relief to be done. Thanks again. I hope you enjoyed. =)