A/N: This is the last installment of the 'Tense Trilogy.'

Castle & Beckett

"Beckett?"

Her whole body stills, the sound of the familiar voice sending a shiver down her spine.

The detective lifts her head and turns to see Ryan and Esposito. She blinks, realizing. Esposito.

"What?" she says reflexively.

"I said, what the hell are you two doing on the floor?" Esposito repeats. "Hold up, is Castle okay?"

She looks back at the writer, ready to collapse with grief, only—

She double-checks her hands, flipping them back and forth to make sure she isn't seeing things, but no, there isn't any blood. Impossible. There's not a drop on Castle, either. How? She skims her fingers over his upper torso, searching for the bullet wound near his heart but it seems to have vanished. It's gone, she concludes. The writer looks like he's asleep.

"Yo, do we need to call the paramedics?" Esposito asks.

"No, uh, Castle fainted," she supplies, her brain not quite processing this new development. She just watched him bleed out. Was he really alive? She instinctively feels for his pulse, finding a strong and steady beat. A grateful sob tears up her throat.

"Jeez, Beckett, are you alright?" Ryan asks.

She ignores him and pats Castle's cheeks. The writer's eyes immediately flutter open and she whispers a thank you to the universe, quickly palming away the moisture in her tear ducts as she gathers her composure.

"Can you grab him some water?" she asks, "I think he's dehydrated."

Ryan scampers toward the break room as she worries her fingers against Castle's shirt collar.

"What happened?" the writer asks as he comes to and rubs the back of his head.

"You…fell," she says flimsily.

"Here, take my hand," Esposito says, offering his forearm to the writer. Castle latches onto the Latino detective and leverages himself to a standing position. Beckett hides her smile as the writer does a double-take.

"Javi?"

"Hey, man, what's up?"

"How the hell—" he doesn't finish his sentence, instead grabbing Esposito in a tight hug. "You're okay?"

"Of course I'm okay, why wouldn't I be?" Esposito asks, squirming out of the writer's embrace. He swivels his gaze between the pair inquisitively.

Ryan returns. "What'd I miss?" he asks, handing the water to Castle who gulps it down.

"Thanks."

"Does this mean you guys made up?" Esposito asks.

"How do you mean?" Beckett asks, rising to her feet.

"We sent Castle to Harlem, thought you guys could talk things out…" he trails off as he clocks their outfits, "Are those the same clothes you had on earlier?"

"Sorry, did you say you sent Castle to Harlem?" Beckett asks.

"Yes, but I'm still wondering about the clothes thing," Ryan says.

"What's the date today?" Castle asks.

The boys share a weird look.

"June 25th."

"2010?" Beckett presses.

"Yeah...are you okay?"

"More than okay," Beckett says as Castle exclaims, "We're back!" They throw their arms around each other in a celebratory hug, even pulling the boys in, not caring how odd it seems.

"Did you guys get high or something?" Esposito asks, struggling to break away.

"Or something," Castle says with a dopey grin.

"So my mom…" Beckett starts but she can't finish the thought.

"Your mom? Did you find a new lead in her case?" Ryan asks, stepping out of their grip.

Her case. Beckett looks at Castle, a sharp pang of grief hitting her in the chest. She was gone. The writer reaches for her hand, pressing his palm against hers reassuringly.

Ryan notes the exchange between them. "Maybe we should give them a minute," the Irish detective says, sharing a glance with Esposito. The Latino detective arches an eyebrow but doesn't push further and follows his partner towards the break room.

When they're out of eyesight, Castle checks his chest for bullet wounds.

"You're okay," the detective says, smoothing a hand over his shirt.

"We should talk."

"Not here," she says, glancing at Montgomery's office, a mix of emotions swirling in her chest.

They both look back at the elevator.

"Stairs?" Castle says.

When they spill out onto the sidewalk, the sun bears down on them and the air fills with the loud blares of wailing traffic. Without warning, Beckett starts to feel the press of panic on her chest, the weight of it constricting her lungs.

"Cas—" she manages, clawing at her throat, the heat and noise suffocating her, everything feeling familiar yet strange.

He immediately guides her into the shade of a nearby alleyway. He helps remove her coat as her hands find her knees and she bends over. He gently rubs her back, murmuring calming epithets.

"How?" she chokes out.

"How did we get back?" he asks and she nods, trying to find a breath. "My dad said there are multiple Gateways—places that have pockets of meaning for us. The precinct elevator definitely fits the bill. And we had our intentions set to go home, right?"

She nods again, gulping in some air. After a moment, she wordlessly points at the wedding ring he still wears.

"Are you thinking we might be in another parallel?" he asks as she straightens and leans against the brick, her breath coming in short pants. "The boys recognized us. They knew about your mom," he says. "And they said they sent me to Harlem. That's where we were the day we left. This is home. I can feel it," the writer assures her.

She lifts her arms as if to reach out to him and he steps into her embrace, holding her tightly to himself. Her eyes slip shut as her head falls to his chest, listening to the steady beat of his heart. He wasn't dying. She repeats the thought until the weight of panic lifts and her heart rate slows. She can breathe again.

He wasn't dying.

She raises her head, locking her gaze with his.

"You okay?" he murmurs.

"I love you," she says.

"You—?"

"I love you, Rick."

His face lights up when it finally registers with him. "So it wasn't a dream."

"Not a dream," she says with a smile.

"I should get shot more often."

She frowns, hitting a fist into his shoulder.

"Don't you ever do that again," she orders. "You're not allowed to take a bullet for me, got it?"

"Kate—"

"Promise me!"

"I'm not going to promise that," he says softly. "I won't risk losing you."

Damn, him.

"I can't lose you, either."

"Whoever gets there first?" he suggests as a compromise.

"At least wear a vest next time?" she concedes, knowing she's not going to win him over anytime soon.

"Deal," he says, smiling.

"You're the worst, you know that?"

"But you love me anyway," he replies with a grin.

"Against my better judgment," she says on an airy sigh, her arms looping around his neck. His head bends down then and she surges up to meet his lips with hers in a passionate kiss. Urgency builds between them but the detective remembers where they are. "In public," she breathes out, trying to ignore the coil of arousal in her abdomen. Castle reluctantly pulls away, resting his forehead on hers.

"Do you think they're back, too? Our Parallels?" she asks to distract the both of them.

"I don't know. I hope so. But if we're back in our primary on the day we left, does that mean we never left at all?" he posits.

"Good thing we know someone who can verify," she says, grabbing her phone from her back pocket.

"Hey Dad, thanks for coming," Beckett says as her father slides into their booth at Remy's. She had texted the boys she was taking the rest of the day off, saying she wasn't feeling well.

"Hey, Castle. Nice to finally meet you. Heard a lot about you," Jim says, shaking the writer's hand.

"Good to meet you, too, sir," Castle says cordially.

The pair look at each other, unsure how to start.

"This is going to sound really strange, but is this actually the first time you've met Castle?" Beckett asks, leaning forward.

Jim lets out a lengthy sigh. "I was wondering when this day would come." He reaches for his messenger bag and pulls out a manila envelope, pushing it across the formica table top.

The detective takes it, confused, tugging out a pair of photos. She and the writer stare wordlessly at the mugshots of themselves from '77.

"How did you—" Beckett starts.

"Buddy in records," Jim answers. "Someone had to scrub you from the system. Couldn't have that popping up on your background check when you applied to the Academy."

"We gave fake names," Castle says.

"But they took your fingerprints, right?" Jim says.

"And they keep records of those going back to the 40s," Castle says, catching on.

"These are the originals. I made sure there weren't any copies."

"So it was real. You met us in '77," Beckett says.

"Yes."

"So mom knew and she still…"

"I fought her tooth and nail about it. But she said it had to happen." Jim pulls out a smaller envelope from his jacket pocket. "It's all in here."

Shaking, Beckett picks up the letter addressed to her. It's crumpled and blotted with tears and alcohol stains.

"Do you know what it says?"

"She made me promise to wait. Said I couldn't look until you came asking," Jim says.

"I don't understand."

"She gave it to me the day she died."

Beckett's eyes widen. "So the name of the person behind her death could be in here—the key to unlocking everything—and you never opened it?"

"I wanted to so many times. But it was the only thing I held onto. Keeping that promise. Even when I lost myself in the bottle and watched her case consume you whole. It was her one wish."

"But why didn't she choose to stay? Why leave us?" Beckett asks, her voice suddenly small and broken.

"Because she loved you."

"That doesn't make any sense!"

"Read it when you're ready, Katie girl."

He nods curtly at Castle and gets up to leave.

"Dad, wait," she says, wiping at her eyes. "I have something for you."

Beckett takes out the scrapbook from her inside coat pocket and passes it to her father. His brows scrunch together as he takes it, sitting back down.

"What is this?" he asks.

Beckett takes a breath and replies, "Before we came back here, Castle and I went…somewhere else. Another universe. A parallel timeline."

"Come again?"

"Mom was alive there."

His eyes expand as he stares down at the album. His hand tremoring, he opens it, freezing at the sight of an older Johanna laughing on a picnic blanket with Fitz in her lap.

"Who's this?" he asks, pointing at the baby.

"Long story," Beckett responds.

He continues flipping through the album, awestruck. When he reaches the end, he spots the corner of a white paper sticking out of the back flap. He eases the paper out, discovering his name on the front of a folded note.

He glances up at the pair before opening it, his eyes eagerly tripping over the words.

Then he does something the detective hasn't heard in a while. He laughs—loud and full-bellied, the note falling from his grasp onto the table.

Curious, Beckett reaches for the scrap of paper and scans it. Castle reads over her shoulder.

James, honey—

Katie says you're still single...you've always been too honorable for your own good.

But you don't need to be such a blockhead.

If romance is too hard, at least find someone to go fishing with.

No one said you had to be alone. Don't be an idiot.

Love you until the scales fall off.

Yours,

Jo

"Scales?" Castle whispers to her.

"Scales of justice. Lawyer thing," Beckett answers quietly.

Jim palms some wetness from his eyes, returning his attention to the couple.

"Thank you," he rasps.

"Can I get you folks something?" a voice interjects. Everyone snaps their gaze to the woman in an apron and updo.

"No way," Castle says, recognizing their waitress from '77. "You're still here?"

"Excuse me?" Patty says, noticeably older with ashy blonde hair and crow's feet and still a beauty.

"Did you waitress here in the late 70s?" the writer asks.

"Matter of fact, I did. I'm a part-owner now but I like to help when things are slow. What's it to you?" the blonde challenges.

"Nothing, uh—" the writer fumbles.

Beckett snorts.

"You know, we were just heading out but my father would love someone to share a cup of coffee with. Or maybe a muffin," she says, rescuing Castle from his misery.

Patty assesses Jim.

"That so?"

Jim glares daggers at his daughter.

"Don't be an idiot," Beckett quips, grinning, as she scoots out of the booth with Castle.

The detective glances back as they exit the diner and watches Patty take a seat across from her dad.

"Who knew you were such a romantic?" the writer says, placing an arm around her shoulder and dropping a kiss on the top of her head.

"Think she knows how to fish?"

She and Castle both stay silent as they drive to the loft in her cruiser, their minds wandering, trying to unravel the complicated web of events.

The writer unlocks the front door, calling out for his daughter and mother.

"Aren't they in the Hamptons?" Beckett asks.

"You're right. I completely forgot. Mother is at the beach house, and Alexis just started her Princeton summer program."

"Are we really here?" she asks rhetorically, collapsing onto his couch, a wave of exhaustion rolling over her. The writer asks her to scooch so he can join her and positions himself behind the detective, his arms coming to surround her.

She lies in his embrace for a while, feeling safe. Until her cell rings, startling them both.

"Ignore it," Castle says.

"Could be the boys."

He grumbles into her neck.

"Beckett," she says, answering the call.

"Hey, Kate," a male voice says and she sits up as if hit by a lightning bolt.

"Josh?"

"Who's Josh?" the writer whispers loudly.

Beckett covers his mouth with her hand. "Oh my god, Josh. Hi."

"Hey, I was on a break and wanted to check in, make sure we're on for tonight," the doctor says.

"I'm glad you called, actually. Um..." she looks at Castle, fighting the urge to laugh at the absurdity of it all. "I had something come up."

"Rain check then?"

"Oh. It's…well, it's more like I had a someone come up. Someone from my past and—"

"Say no more."

"I—"

"It was nice meeting you."

"You, too," she says, "Bye."

Castle lifts the phone from her hands, hanging it up.

"Someone from your past?" he asks with a raised brow.

"Past, present, and future," she says.

"Can this future include a vacation?" he asks.

"What kind of a vacation?" she asks.

"I heard you like the beach," he says, sitting up and sweeping some of hair behind her ear. She feels like a schoolgirl getting asked to the dance when he adds, "Do you want to go to the Hamptons with me?"