Prompt: 'Castle or Beckett is a secret service agent to President Castle or Beckett.'

The terrorist attack on the White House comes totally and utterly unexpected, in sync with the wave of horrific explosions and decimation sweeping over a slew of major cities across the nation.

And all he can think about is the job he's had for the last four years: keeping her safe.

Rick Castle, head of the secret service team assigned to protect President Beckett, moves into action the second the missile hits the East Wing of the White House. He hustles Kate out of the Oval Office and scans his eyes over the unfolding chaos before it can touch her.

"Castle," she gasps, jerking on his hand, slamming them both into the wall as a spray of bullets begina to rain through the air.

"Shit," he breathes, withdrawing his own piece, aiding in the returning fire of his team, trying not to watch the bodies of government officials falling dead in the halls. "Go ahead of me. Keep going-"

"No," she hisses, her fingers hooking at his forearm, and he growls, hates now more than ever how stubborn she is.

"I'm covering you, go," he commands, keeping both hands on his gun, his arms in position as she leads them down familiar corridors.

At least she knows the drill, isn't trying to be a hero-

He hears her grunt, the slam of her body into another wall.

Castle immediately spins, sees her pinned by a man in all black riot gear and a gloved hand around Kate's throat, a knife in the other.

Her knee pistons up into the man's groin, has him doubling over just as Castle fires the shot into his head.

"Are you okay?" Castle questions, hearing the wheeze of her lungs as she coughs, but she's already nodding, returning to the mission at hand, running.

She waits for Castle to unlock the panic room with his gun cradled in her palms, her heart rabbiting but her finger steady on the trigger as she waits with bated breath.

"Okay, we're in. Hurry, before someone sees," he murmurs, his hand at the small of her back.

Kate lowers the sig, but doesn't give it back until they've slipped inside the secret room embedded into the wall, until the door that blends all too perfectly with the wall slides back into place.

Castle is one of the only people on the planet who knows about the panic room, one of the selected few allowed to know, and probably the only person she's always trusted would never turn on her.

He proves her right.

Castle keeps one hand on her arm as they descend down the stairs, the pathway long and dark, foreboding. She feels the cool air embrace her the lower they travel, the weight of moisture clinging to her skin.

The underground safe room was built over a mile deep and by the time they finally reach the floor, the second security enclosed entryway, she's panting.

"You okay?" he asks, his own breath quickened, his eyes glimmering in the barely lit corridor.

"Let's just get inside," she murmurs, but Castle lifts a hand to her face, his palm a familiar fit to her cheek.

"We're surviving this, Kate."

"Maybe, but no one else is," she mutters, scraping a hand through her hair. "I ran like a coward. I'm supposed to keep these people, this country, safe-"

"By dying for your cause? Because that's all you would have accomplished up there," he reminds her with a narrowed look. "We've gone over this multiple times-"

"Doesn't make it easier," she snaps, stepping away from the caress of his hand and punching the code into the lockbox. "How long are we staying in here?"

"As long as it takes," Castle sighs, following her in as the vaulted door swings open. He slams it shut behind him and enables every lock equipped to withstand all forms of enemies. "We should have electricity down here, so I can have eyes on the outside."

She reclaims his hand again as they start down the final corridor that will lead them into a safe room the size of a studio apartment, stocked with food and weapons, and hopefully enough hard walls to keep them alive.

He laces their fingers, squeezes a little too tight, but she welcomes his firm grip, the confirmation that they've survived. For now.

Kate is curled on the sofa against the wall, her heels and pantsuit gone in favor of jeans and a black sweater, boots better suited for running, fighting. He's trained with her for years now, knows she can hold her own against a man twice her size. But right now, with a throw blanket he knows once belonged to her parents tugged up to her chin and her eyes so hollow, she looks so small, fragile.

Castle was recruited to lead the security team for President Beckett during her first month of presidency, his knowledge of terrorism after losing both his mother and daughter in the 9/11 attacks profound, aiding him in his career in counter-terrorism.

He didn't want to work in secret service, to spend his days guarding some woman, but then he met her. He made the deal to work for a year with her and then act on the opportunity to return to his original unit. But after getting to know Kate Beckett, learning her story of rising from homicide detective to senator, the source of her drive born from the grief of losing her mother, he chose to stay.

He chose her, always her.

"Thank you," she murmurs after he's set up the security feed and finished sorting the guns and ammunition he stocked down here over a year ago.

Castle glances up from a pile of grenades, rises from his haunches, and mutes the monitor showing them a live feed of the horror unfolding across the property. "For what? Getting down here was a mutual effort."

"For keeping me safe, not just today," she answers, biting down on her bottom lip. "For making this job more bearable."

"You've been an amazing leader, an extraordinary president," he says, his brow still knit in confusion. Her job was the most stressful position in the world, but she's good at it, and he thought she enjoyed it. "You've done right by the people, by justice. Today? This was completely out of your control, Kate."

She sighs, not wholly convinced, and Rick crosses the room to ease down next to her.

"Stop thinking like the president, hoarding all the guilt," he murmurs, earning the turn of her gaze, the shift of her body towards him. "Just be a normal human being who survived nearly being assassinated. You're alive, that's all that matters."

"What about you?" she inquires, her knees bumping his thigh as she faces him now. "Castle, I hate that your entire life has become centered around protecting me-"

"Even if this wasn't my job, it's what I'd be doing," he states, shutting down that line of thinking before it can begin. "Keeping you safe… it's all that matters to me. You're - you already know."

Kate raises her fingers to graze along his cheek and he catches the back of her hand, turns his lips into her palm. It's been too long since he's had the chance to touch her.

"I love you too," she whispers, leaning in to nudge her nose to his cheek. She sighs out in familiar appreciation when he brushes his lips to her mouth, buries his fingers in her hair and deepens their kiss.

Kate's soft moan has him desperate for more, but he remains glued to the spot, waiting for her to make the first move even as he suckles on her bottom lip. All it takes is a stroke of his tongue over hers to gain the surge of her body in his arms.

"I think it goes without saying that I'm done hiding it," she mumbles, dragging him down on top of her, cradling his body in the embrace of hers.

"Good, because I wasn't sure how we were going to make it another four years like this," he breathes, smirking against her mouth when she chuckles. He chokes on a groan when her hands slide beneath his shirt, splay at his shoulder blades. "Kate, I should-"

"Remind me why I'm alive." He drops his forehead to rest against hers, closes his eyes to the flames of sensation she elicits with the innocent touch of her fingers down his spine. But he's helpless when her mouth opens beneath his, when her chest lifts to press against his. "Rick-"

"You're alive because you're too good to die," he mumbles, kissing the skin between her brows, dusting his lips down her nose. The whimper that climbs her throat is muffled by the kiss he layers to her mouth. Her ribcage stutters beneath his hands as he skims his palms to her flesh, caresses the taut muscles and sinewy curves of her body. He should be watching the door, guarding her, but the world is crumbling around them and all he wants is this, her. "Because I love you too much to let you, Kate Beckett."

She remains tangled with Castle on the couch for a long time. Her eyes often drift to the monitor on the table across the room, to the chaos that has gone quiet, but the White House grounds are still roamed by murderers. She knows she has responsibilities, duties as a leader of the country, but Castle has a point - the only thing she can accomplish by taking any course of action now would be adding to the bloodbath with self-sacrifice.

Castle has explained their exit strategy and has plans to communicate - once the chances of having a phone call intercepted have lessened - with Ryan and Esposito. The two secret service agents have apparently owned a role in this emergency game plan concocted between her three men since the early days of her presidency.

"They love you too, you know," he murmurs the explanation into her hair while he brushed his hand up and down her spine.

She nods before lowering her head to his chest, fighting off thoughts of loved ones, her lack of them. Her mom's been gone for fifteen years, her dad passed last September. Castle's been without his eight year old daughter, Alexis, and his mother, Martha, since long before she ever knew him.

The list of those she cares about has only continued to shrink, but her ferocity to protect those she has left has grown.

Kate curls in closer to him. "We're a family."

Castle's fingers bury in her hair, circle along her scalp. "Does that explain why they call us mom and dad?"

She scoffs, turns her head to brush her upturned lips to his collarbone.

"We have contacts across the globe," he picks up, circling back to their original conversation. "They'll send reinforcements. It's just a waiting game right now."

"If we get through this, I don't want to run again," she confesses, feeling him shift beneath her, attempting to catch a glimpse of her face, but she keeps her cheek pressed to the spot above his heart.

"This isn't a new idea, is it?" he murmurs, curving his palm at her nape. She shakes her head.

"I want to change the world and I - I feel like I had a good run these last four years, but this job… I'm tired, Rick. And after this?" She sighs, unfurls her arms from her chest and lifts her head to meet his eyes. Soft and understanding and so very blue. "I just want to live for me for a little while. I want to go back to New York and collaborate with the NYPD again, I want - I want to get a loft in the city and a beach house in the Hamptons like the one you always gushed about-"

He huffs a laugh, his cheeks warming with a hint of color. Kate balances a hand on his chest, cranes her neck forward to rest her forehead to his, nudge her nose to his cheek.

"I want a life. With you."

"All you've ever had to do is say the word," he replies, stroking his thumb to the hollow spot at the base of her skull. "I want all of that and I - I want to try writing again."

Kate sucks in a breath, can't help the smile. He's been writing her short stories for years now, snippets of characters and enticing political thrillers that she's never been able to get enough of. His writing career was cut short after the national tragedy that took his family and she never questioned it, didn't have to. But to witness his passion for the written word and weaving of a tale renewed… it has her heart fluttering with excitement.

"Man, we really have to make it now," he chuckles, grinning at the press of her kiss to his mouth.

"We're going to make it. We're going to stop the bastards who bombed my house, took strikes at our city, our country. We're going to rise again as a nation, like we always do, and then you and I are getting our happily ever after," she lists, feeling her heart skip and accelerate at how badly she wants it. "And years from now, you can publish a loosely inspired novel about it."

"Ah, President Beckett, you get me."

His phone buzzes from the pocket of his slacks and Rick quickly leans over to snag the device.

"It's Esposito, we need to get ready," he murmurs, his chest expanding with a deep breath as he lifts his eyes to hold her gaze. "You're glued to me the second we step out of here. I'm not letting anything happen to you."

"It's mutual. I've got your back out there, Castle," she reminds him, nodding her head towards the arsenal of weapons. "No more overprotective bullshit. You're my partner."

He sighs, but doesn't argue. "Deal, Madam President."

She shoves lightly on his shoulder as she reaches past him for her clothes. "And stop calling me that."