Disclaimer: I wish I was a writer for the show, but I'm not. Even if I were, all rights belong to the great Andrew Marlowe and ABC.

Spoilers for Linchpin and (slightly) beyond.

Author's Note: Between the hand holding, the ticking time bomb that these secrets have become, the mention of Castle's father, and all the fandom speculation about that note Beckett received in Once Upon a Crime… this was born. I literally dreamed about it last night.

xx

It felt like a pile of bricks had been stacked on top of her chest. She stood in the middle of her partner's office, groping behind her body for the desk, desperate to find purchase in anything that would keep her from collapsing. She knew her mouth was hanging open and she could hear his heavy breathing from his perch less than a foot away. The homemade murder board cast an eerie glow around the darkened room. Her mind was racing as she tried to find words – any words – to break the oppressive silence that had descended upon them.

She jumped when she felt his hand settle on her shoulder. She turned her head quickly, taken aback at the guilt and fear she saw in his eyes. Nothing, however, prepared her for the tear that fell traitorously from the corner of his eye. He almost looked resigned, as if he was sure this would be the last time he ever laid eyes on her and he had to make sure he drank her in as much as possible.

Tearing her eyes from his, she pressed one hand to her forehead as she let her gaze sweep over the information he had collected in the past year. It wasn't much, but it was enough to begin piecing together her broken history. It was significantly more than she had before she was shot, at any rate.

And he had kept it from her. Because… why? She closed her eyes and swallowed hard, willing the knot that had formed in her throat to descend back into her stomach, which was already awash with nerves and anxiety. He had kept it from her because…

"You love me."

Her words were whispered, but they were just audible enough for him to hear. She could almost feel the vibration in her own body when he groaned and put his head in his hands.

"You love me," she repeated, her voice gaining more strength but still dangerously quiet in comparison to her usual tone. "That's why you did this, isn't it?" She turned to him and wrapped a hand around each of his wrists, pulling his hands away from his face, forcing him to look at her.

"I heard what you said, Castle. I never forgot. I've been lying to you. But you know that, don't you?"

The smile that curled his lips might have been the most miserable thing she had ever seen. "I worked it out, somewhere along the way."

"And you still did this?"

He was obviously confused, now. His body appeared to be braced for physical impact, for her to smack him across the face or pound his chest with her fists before she turned around and permanently walked out of his life. He nodded his head, but he remained silent, his eyes locked on hers.

She pulled her bottom lip between her teeth and narrowed her eyes slightly, considering him for a moment before suddenly rising to her feet, guilt pooling in her stomach when she saw him shy away from her. Holding out her hand and linking her fingers with his, she pulled him to his feet.

"C'mon, Castle. I need to show you something."

xx

The ride to her apartment was silent. He sat in the passenger seat, staring out the window with a sullen, drawn look on his face, but his fingers remained linked with hers as their hands rested on the gear shift. She kept sneaking glances out of the corner of her eye, and she didn't miss the reappearance of a tear snaking its way down his cheek every so often. He let them fall for the most part, occasionally using his other hand to swipe at his eyes in agitation.

She squeezed his hand when they pulled up in front of her building, only letting go of his hand long enough to exit the car and meet him on his side of the car. He started to move toward the front door, but she kept a firm grip on his hand, rooting him to the spot. Tentatively, she raised her hand, pleased when he kept himself from flinching, and gently wiped the last tear off of the skin just below his eye.

"They aren't a sign of weakness, you know," she said in a low voice. "You taught me that." And then she was gone without waiting for a response, almost pulling him toward the building and into the lobby. He didn't dare ask questions as they rode the elevator up to her floor, and even though his palm was sweaty from being pressed against hers for so long, he made no effort to break the contact.

She wasted no time on pleasantries when she let him into her apartment. Didn't kick off her shoes, offer to take his coat, or tell him to help himself to the drinks in the refrigerator. Instead, she continued walking until she was standing in front of the shutters he knew held her own homemade murder board.

It was then that she let go of his hand, turning slightly sideways and glancing up at him. He frowned at her, eyes clouded. "Kate… you promised me you would give this up for now. I was trying to keep you safe-"

She cut him off with a finger over top of his lips and a shake of her head. "Don't, Castle. I know all of that already." She moved toward the window, reaching out to pull open the shutters but stopping suddenly and turning back to him.

"You did all of that research, took on all of that risk, because you love me."

It wasn't a question, but he nodded his head anyway.

She took a deep, shuddering breath and stared directly into his eyes. "Then keep in mind that I did this because I love you, too."

His brow wrinkled in confusion, and when she turned to open the shutters, pulling one to each side, he felt his heart leap into his throat.

Gone were the pictures of the dead woman lying in the alley, the headshots of her mother and her colleagues, and the carefully scripted case notes detailing every aspect of Johanna Beckett's murder. In their place hung a series of scribbled notes, written on scraps of paper, post-it notes, and even napkins. Pieces she had picked up during late nights at the precinct, favors called in to friends and colleagues. As his eyes scanned the board, bits began to leap out at him.

Martha Rodgers.

New York City

Disappeared.

1971.

CIA.

Washington D.C.

She watched as his eyes grew wider and wider, finally coming to rest in the center of the window, where a shadowed silhouette of a man was taped and labeled as John Doe, a garishly bright orange sticky note neatly attached to one corner, asking the question she had so obviously been trying to answer:

"Who is Rick's father?" he read aloud, visibly cringing at the shakiness of his own voice.

She shrugged her shoulders, now afraid to meet his gaze. She heard his footsteps as they approached the window, but was surprised to feel his fingers under her chin, lifting her head so that they were face to face.

"You've been searching for my father?"

She gave him a watery smile, unsure when it was that she had begun to cry. "I'm trying. He's not being very cooperative."

"Must be in our genes," he said softly. "I'm sorry, Kate. I'm sorry I couldn't tell you about what I was doing until now. I wanted to. I almost cracked a dozen times."

She nodded and he realized her chin was still held captive in his hand. He carefully moved so that he was cupping her cheek instead, his thumb tracing soft patterns on the skin there.

"Castle… Rick…. I don't know what to say. I don't know what all of this means. I can't even begin to try to figure it out."

He shook his head. "It doesn't matter. We can worry about that later. What I care about right now is the fact that I am completely in love with you, and I think you just admitted that you love me too."

She huffed slightly, admittedly a bit put out to have been put on the spot, but her eyes were shining with more than tears as she stared back at him. "Secret's out, I guess."

It felt wrong, the fact that they were able to laugh as he pulled her into a hug, crushing her against his chest and turning them both away from the window. Then again, she thought to herself as she nuzzled her face into the warmth of his body, when had they ever been ones for convention?