It took five years, two weeks, and one day for Bellamy to find Clarke after she slammed the heavy metal door in his face and locked herself out of the bunker. In all that time, trapped inside with the other Skaikru survivors and waiting for the radiation to subside, he never allowed himself to believe that she was dead.

She had looked fiercely at him through the window in the door as he pounded on the glass, yelling for her to come back in, to save herself, to let him shoulder this burden.

Tears were gliding down her cheeks, but she made no move to open the door. Instead, she mouthed three words to him through the glass. They weren't the three words that he wanted to hear, that he had been aching for months to say to her himself. Still, they would echo in his brain every night for the next five years as he struggled to fall asleep: "Stay alive, Bellamy."

He answered with three words of his own, a promise based on the stubborn belief that she would somehow manage to survive. "I'll find you."

She pressed her hand briefly against the window, nodded, and shut the outer door. He heard the sharp hiss of air as Clarke activated the hermetic seal from outside. More faintly, he heard the metal clicking of the third door's spinning wheel mechanism, and then the heavy thud of the triple-reinforced steel doors beyond that. He couldn't hear anything else, but he imagined her making her way back through the maze of hallways, shutting and sealing every door as she went. And she was gone.

He never forgave himself for not realizing what she was planning. In retrospect, he ought to have been suspicious that she agreed so easily to let him be the one. As soon as he understood the sacrifice that would have to be made—one life risked and probably lost, in order to protect the rest—he resolved to do it himself. He was quick and resourceful, he reasoned, and maybe he would have a fighting chance at locating some last-minute shelter from the incoming wave. Of course, beneath all that reasoning, he knew it was a long shot. The person who sealed the door would never survive. They decided between the two of them not to tell the others. Their people had finally found the refuge they needed. The relief from the constant hum of dread that had haunted them all for months was too sweet to darken with this terrible choice.

So when the time came, Bellamy steeled himself for the end by circling the bunker, taking in the faces of all the people he would be protecting—the people who deserved to survive. Monty and Jasper, chuckling together over some private joke. Octavia, curled under a blanket and sleeping peacefully for what must have been the first time in months. He didn't dare wake her and disturb that hard-earned peace. Raven, fiddling with an old radio and talking animatedly to Kane.

And Clarke. He caught sight of her on the opposite end of the wide entrance hall in hushed conversation with her mother. As Bellamy watched, allowing his gaze to linger on the burnt gold of her hair, the firm set of her chin, the intensity in her eyes, Clarke clasped Abby in a brief but tight embrace and whispered something in her ear.

Abby jerked backward, looking distressed. She started speaking frantically, shaking her head and raising her voice as Clarke disentangled herself and started backing toward the door. Then Clarke lifted her chin and met Bellamy's gaze across the room, and his heart dropped because suddenly he knew.

He broke into a sprint, leaping over cots and scattered possessions, his heart a battering ram against his rib cage, one desperate word reverberating behind his ears: No, no, no…

If he had only understood a moment earlier, or if he hadn't been so far away, if he had run more quickly, if he hadn't briefly halted his momentum to avoid careening into a small child who toddled into his path, he might have managed to stop her. But he didn't reach her in time, and when he skidded around the final corner with a breathless "Clarke, don't…!" she was already shutting the door and pulling down the heavy metal latch.

When they finally set themselves free, unsealing the many tiers of airtight doors and spilling out into the open air—after five endless years, plus a few agonizing weeks of air quality tests and water quality tests and intense worry that no matter how long they waited, it would never be enough time for the radiation to clear—Bellamy immediately set out in search of her. He had promised, after all, and he had stayed alive through five full years, feeling her absence like a hole in his lungs, like a splinter in his eye, like a bullet lodged in his gut.

No one tried to stop him. No one even tried to slow him down. He was Bellamy, after all, and she was Clarke, and they wouldn't be themselves unless they were searching for each other. They had all watched him for the past few weeks vibrating with a desperate energy, packing and re-packing his things, poring over maps, muttering to himself about the second bunker, 1.77 kilometers, the obelisk beside the statue beside the river.

This had been their last hope as they searched for salvation. Conspiracies hosted on old, archived web pages, plus a healthy dose of luck, had led them to the bunker where Skaikru had survived for the last half-decade. The bunker was buried deep beneath an expansive but crumbling white mansion, so overgrown with vegetation that Bellamy nearly broke his ankle tripping on a half-buried metal rectangle marked Pennsylvania Avenue in faded block letters. Those same websites had whispered about another bunker, constructed for the wealthy and the powerful, hidden deep below the great obelisk that had once towered over a capital city. It was just over a mile away. When they found the first bunker stocked with a decade's worth of food, equipped with water and air filtration mechanisms, with enough space to comfortably house all of the straggling survivors, they didn't feel the need to investigate the obelisk bunker. But that must be where Clarke had gone. It was close by, and she wouldn't have had much time. If the circumstances were just right—it wasn't even that far a reach, to think that the other bunker would be stocked, and livable, and (please please please) sealable from the inside—she could have made it. She must have.

Bellamy crashed and trampled through the woods, his heart slamming a familiar rhythm against his ribs (Clarke, Clarke, Clarke). His eyes were on the horizon and his mind was twenty minutes in the future, when he would locate the obelisk and unseal the bunker and find her there safe, healthy, breathing. He was so focused on the bubble of hope welling in his chest that he leaped instinctively over a small animal huddled in his path. Then he skidded to a halt and wheeled around to stare at what was unmistakably a tiny, lost-looking child.

This was not a child from the bunker. He was dressed in what looked like Grounder attire, his tiny frame swallowed by a soft fur overcoat. He couldn't have been more than four years old. The child stared at him with huge brown eyes but didn't move or speak.

Bellamy's heart urged him to turn around, keep running, go find Clarke, but as he gazed around the forest clearing he realized there was no one at all in sight. Where were this child's parents? More importantly—who were his parents and how did this child exist? He was small enough that he must have been born after the radiation wave hit.

"Uh…hello," said Bellamy uncertainly, edging closer, cautious in case he frightened the boy. "What's your name?"

The boy didn't answer, just sniffed quietly and reached out stubby arms toward Bellamy. Bellamy's heart ached with a sudden flash of memory: a four-year-old Octavia, giggling and reaching her arms out to him, wanting to be held. Without thinking, he scooped up the child and balanced him lightly on his hip.

"Okay, buddy," Bellamy said, "we need to find your family. You've gotta belong to somebody, right?" The child looked solemnly into Bellamy's eyes and hiccupped.

There was a horrible suspicion forming in the back of Bellamy's mind, one that he realized had started creeping in the moment that he threw wide the bunker's outermost door. His eyes had been dazzled first by the blazing sunlight, and then by the brilliant green of the trees. Now, standing in the quiet clearing, he heard birds chirping, insects humming, small mammals moving through the underbrush. This was not the grey and ashy nuclear wasteland that he had been expecting. He hadn't given himself time to think about that before, as he was sprinting through the forest with his mind on Clarke. But now—how was it that this forest ecosystem seemed fully recovered from a wave of radiation that ought to have burned it to the ground?

A faint buzzing in the distance caught Bellamy's ear, and he cocked his head toward the sound. In his arms, the boy imitated the motion of Bellamy's head, tilting his chin to the side and smiling with some unexplained delight. The corner of Bellamy's mouth curled upward into the ghost of a smile. When was the last time he had smiled? He hitched the child higher on his hip and began to make his way toward the distant noise.

As he grew closer, the buzzing shaped itself into human voices, many voices overlapping, laughing, shouting, singing. A few moments later, he emerged into the middle of a bustling marketplace in a Grounder village.

He blinked with surprise and hesitated at the edge of the milling crowd, absorbing the implications of the scene. There were at least a hundred people jostling about the square, haggling over wares, lounging beneath the shade of trees whose verdant foliage was very much alive. There were no signs of radiation here, at least not visible ones. To his left, a group of children splashed in a stream and shrieked with laughter.

A young woman looked at him curiously, then said something in rapid Trigedasleng.

"I'm sorry," Bellamy replied, struggling to follow. "I don't understand." He adjusted his grip on the child, who was snuggled sleepily against his chest. "Does he belong here?"

The woman stared, eyes shifting from Bellamy's face to his jacket to his holster. "Skaikru?" she asked, sounding excited.

"Yes," Bellamy answered, "Yes, Skaikru. Do you know…?"

But the woman had turned excitedly and was shouting at the crowd. Several people paused, stared, and then started shouting back in return. Bellamy listened helplessly, five years of isolation with his own people leaving his already poor Trigedasleng too rusty to comprehend what was being said. But his heart leapt when a particular word started to pass through the crowd…a word that sounded very much like "Clarke."

Several people crowded around him and started guiding him by the elbow out of the market square. A few young men ran ahead, shouting and jostling each other, and now there was no mistaking it, they were yelling a single word again and again and it sounded so very, very much like her name. He didn't dare believe it, though. There was probably a word in Trigedasleng like klark that meant "visitor" or "stranger" or "Hey neighbor, this weird guy just wandered into our village carrying your kid." He couldn't believe it. He didn't dare to.

But then she emerged from behind a hut, looking frazzled and slightly tearful. A huge, dazzling smile lit up her features and she broke immediately into a run. Bellamy had never felt such a dizzying rush of emotion—shock, relief, joy, affection—and then, confusion, as her gaze focused on the child on his hip and she swung the boy into her arms, cupping his dark curls protectively and gasping with giddy relief, "Gus! Gus! I was so worried, where on earth did you go? I can't believe—"

The words died on her lips as she raised her eyes to meet Bellamy's. She swayed slightly on her feet, mouth hanging open, eyes shining with shock, relief, joy, affection.

"Bellamy?" she breathed, her eyes running over his face, his chest, his arms, down to his feet and back up again, as though unable to believe that he was really there. Then she threw her free arm around him and buried her face in his neck. "Bellamy," she breathed out, and he breathed in, the scent of her skin where her neck met her shoulder bringing the memory of the last time that they were this close rushing back to him.

The day that they found the bunker beneath the big white house was the happiest he had allowed himself to feel in years. Behind every door was a new gift—food stores, running water, wide mattresses, soft pillows. He and Clarke spent hours exploring the maze of hallways and rooms, checking and double-checking that it was safe, clean, and secure.

They radioed back to camp, telling Kane and Abby breathlessly about their incredible good fortune. They were just heading back to the rover, which was parked a few minutes' walk away, when thunder crashed in the distance and ominous dark clouds began rolling in.

"Back inside, quickly!" Bellamy said, ducking his head against a strong gust of wind. Tiny drops of water began hissing against the ground. They rushed for cover together and huddled just inside the house, staring through the tangled ivy in the broken windows at the sudden downpour of black rain.

"We'll have to wait it out," Clarke said, shifting anxiously from foot to foot. "It looks like it will last a while."

With nothing better to do, they continued to explore the bunker, beginning to strategize about how to ration the food, assign the living quarters, and keep people sane and productive. Inside a block of what looked like office spaces, they stumbled upon a wood-paneled room with a long leather couch and a mahogany desk. A golden placard glinted on its surface: Madam President.

"Looks like this should be your office, princess," Bellamy chuckled, showing her the placard.

Clarke smiled and ran a hand over the smooth surface of the desk, but her eyes were distant and she was still shifting her weight uneasily back and forth. Her neck and shoulders looked tight with tension.

"It doesn't feel real, does it?" Bellamy asked, moving closer and resting his hand on the back of her shoulder, his thumb grazing the skin at the base of her neck.

"No," Clarke answered, "it doesn't. I keep expecting something terrible to happen. Some new disaster to keep us running."

"Yeah." Bellamy swallowed. "Something else to keep us apart." His voice came out low and hoarse. Clarke grew suddenly very still, staring at the desk, and Bellamy felt heat rise in his cheeks. He hadn't meant for his words to have such weight behind them, such obvious meaning. Or maybe he had.

She turned to look at him then, covering his hand on her shoulder with her own. Bellamy swallowed again and let himself look—just for a moment—at the smooth, pale skin where her neck met her shoulder. Out of the corner of his eye he saw the hard set of her chin grow suddenly softer, and he found his eyes drawn along the curve of her cheek to her lips.

"Bellamy," she whispered, her eyes locked on his face, and he realized suddenly that he had been staring, really staring, at her lips, and he was still staring and couldn't bring himself to stop. Heat curled in Bellamy's chest and spread across his neck. His breath was suddenly shallow and he felt slightly dizzy, as though he wasn't getting enough oxygen.

After the dropship landed on Earth carrying the first hundred, Bellamy had spent months denying and then actively suppressing the magnetic attraction that he felt to Clarke. And now they had been a team for so long, needing each other for support and back-up and safety, that he hadn't been able to bear the thought that he might ruin their partnership by involving something as fragile and volatile as emotion. But in this moment, with the promise of a safe future finally in their grasp, he decided to allow himself to feel what he had been bottling up for years and—the thought frightened him, thrilled him—to risk letting Clarke see him feeling it. Normally he tried to arrange his features, at least when he knew that Clarke was looking at him, into some semblance of a friendly-platonic expression. But he found it suddenly impossible to mask the raw need that was coiling through every muscle in his body.

So he allowed the hand that was on her shoulder to slide slowly down her arm and curl around her waist, and then he lifted his other hand to her jaw and leaned his forehead against hers, trying to control his breathing and his rapid pulse, but failing miserably. He knew that Clarke could see his chest heaving, and she could probably hear the thump of his heart as it hammered against his ribcage, and even though the part of him that had pictured this moment (once, twice, a thousand times) had hoped that he might sweep her off of her feet with a confident and passionate kiss, he found that all he could manage was to stand there, vulnerable, running his thumb gently along her cheekbone and hoping that she wouldn't back away.

And she didn't. She stood right where she was, her eyes fluttering shut as his thumb moved down to graze her bottom lip. He realized that she was trembling, but he couldn't tell whether it was with exhaustion or nervous energy or (was he fooling himself?) desire. They stood together, forehead to forehead, mouths inches apart but not touching, not yet, until Clarke whispered his name with such aching tenderness that he couldn't stop himself from pressing his lips to her forehead, and then her cheek, and then, finally (finally), her lips.

Clarke gasped into his mouth and wove her fingers into the curls at the nape of his neck, and he groaned at the feel of her fingers on his scalp, the softness of her waist under his hands, and the knowledge that this was real, this was happening, she wanted him too.

He wrapped his arms around her and deepened the kiss, pulling her flush against his body. He couldn't get enough of her—her smell, her taste, the feel of her moving against him, the sound of her shallow gasps. When he trailed kisses down her jaw and into the curve of her neck, she let out a soft moan that set his skin on fire. They shifted against each other, desperate for friction, and then Bellamy lifted Clarke onto the desk and she pulled him close with her legs around his hips until they were pressed together in the most intimate way possible.

Before he knew it, their shirts were discarded in a heap on the floor and she was pressing her bare chest against his. He realized that he was losing all grip on control, and pulled back slightly to catch his breath.

"Clarke, I—god…" He lost his train of thought as her hands moved to the buckle of his belt.

"I want this, Bellamy," she said simply, fiercely, her fingers moving nimbly to the button of his jeans. "I want you."

They were being reckless and impulsive, and he knew it, but it just felt so goddamn wonderful—and, he thought to himself, they deserved this moment, this chance to act like irresponsible teenagers in a world that had forced them to grow up too fast, to become leaders, to bear other people's suffering.

Then Clarke removed the rest of her clothing and wrapped herself back around him and he lost all coherent thought. He spent the next hour in a daze of absolute bliss—of feeling her, tasting her, burying himself inside of her and moving slowly, deliberately, watching for every flutter of her eyelids and memorizing every movement of her hips, feeling the first frantic shaking wave of release wash over her and trying with all of his might to hold himself back as sweet, sinking pleasure rushed through him, spreading from where they were joined, where her hands grasped his lower back, where her mouth latched on to his neck—unable to think anything other than Clarke, Clarke, Clarke and swearing to himself never to forget the achingly sweet way that she murmured Bell, Bell, Bell.

That had been the only chance they had, before responsibilities to their people and the rush of preparations and Clarke's desperate act of sacrifice got in the way. It had been five years, two weeks, and five days since he had touched her.

Now, Bellamy found himself fighting to make sense of this bustling village and the unravaged landscape. "How?" he asked hoarsely. "All of these people…?" Then he trailed off, too dazed to form complete sentences.

"Praimfaya never came, Bellamy," she said. "At least, not here."

Bellamy's chest felt hollow. "I don't understand. Why didn't you—"

"I went to the house above the bunker every day," Clarke whispered. "For months. I pounded on the doors. The steel ones, the triple-reinforced layer, some sort of internal locking mechanism engaged when I closed them. I couldn't get past. I tried every channel on the radio, on the walkie, but I couldn't get through. I screamed my voice raw. No one ever heard me. No one opened the door."

Bellamy felt horror rising in his chest as he imagined how frustrating, how lonely it must have been for her. "How long…?"

Clarke's voice was ragged with emotion. "About six months. But then, I had to leave. I needed…medical attention."

"You were sick?" Bellamy asked, concern furrowing his brow. "Are you better? Do you still need medicine?"

To his surprise, Clarke laughed. "I'm fine. It was a temporary condition." She was smiling, but there were tears shining in her eyes. She pressed a kiss to the chubby cheek of the child in her arms.

Bellamy froze, looking back and forth between Clarke and the child. Gus gazed back at him with curious brown eyes, and Bellamy felt suddenly as though all of the air had been knocked from his lungs. "He's your son? Biologically, I mean?"

"Yes," Clarke answered.

"How—how old?"

"Four years. Three months."

Bellamy did some frantic calculations in his head. He noticed for the first time the way that the boy's thick and curly dark hair sprouted in a hundred different directions; the dusting of light freckles on his nose and cheeks; the small dimple in his chin.

His heart stuttered in his chest as he struggled to come to terms with everything that he had lost in the last five years, and the prospect of what he hadn't known he would gain. Tears spilled over onto his cheeks as he stared at little Gus, who smiled and reached out for Bellamy to hold him.

Clarke leaned forward so that Gus could transfer himself into Bellamy's arms, ruffling her son's hair affectionately.

"You see, Gus?" she said, and Bellamy had never seen her look so radiantly happy. "I told you he would find us. Your dad always keeps his promises."