Prompt (via Castlefanficpromts on Tumblr and Anonymous): After 6x23, Beckett goes to sleep regretting all the time she lost with Castle. The next day Beckett wakes up and she's in the body of her 1x01 self.

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A/N – I've had this prompt for a while, but it's taken me a while to get to it given my other stories. A few things you should know about this: First we'll mark this as AU completely, and say Castle dies in 6x23. This, however, is not a death!fic, but instead is about a little bit of time travel. This first chapter picks up right after Lanie confirms Castle's death to Kate. I love happy endings and despise death fics, so I promise that in the end Castle won't really be dead.

Second, I'm not going to get into the whys and hows of how she ended up back in her 1x01 body. I'm a SciFi nerd, and love time travel stuff, but I'm neither clever nor intelligent enough to come up with a way that this might have happened. So we'll just say it happens. You'll see what happens in chapter two.

Third, this first chapter is very much angsty, so be prepared. The fic itself will have lots of fluff, as the whole point is Caskett.

Fourth, I've changed some details of each case that I'll cover in this fic, mainly because I don't want it to be the same as it was in canon. Call it the butterfly effect, she's there from the future in a way, so some things are going to be different. If she knew the outcome of every case it wouldn't be fun.

Finally, I have not one clue how long this fic will be. It could be very long or it could be relatively short. I'm going to let the characters decide, that usually works out the best. As always, leave reviews to let me know how I did and tell me where you'd like the story to go! I love reviews!

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Chapter One

He couldn't be dead. They were supposed to be getting married right now. This couldn't be happening given all they had been through to get here. They had survived serial killers, bombs and dirty bombs, freezers, and they had survived her stubbornness and issues. They were getting married. He couldn't be dead.

"I'm so sorry, Kate," Lanie said, moving to hold her best friend in a tight hug. They were both in the morgue. Lanie had just given her friend the worst news someone could ever receive. Both women had tears running down their cheeks. Beckett stood their completely lost, he hands shaking, looking at the body that was covered by a sheet nearby. Her fiancée. Her lover. Her best friend. Her Castle. God.

"How could this have happened, Lanie," Kate sobbed, her knees almost giving out.

"I don't know, Kate. We'll find out. I promise. I'm so, so sorry," Lanie said, her voice unsteady. She knew her apologies meant nothing; that they could change nothing, but she didn't know what else to say. There was nothing to say. Castle was dead. And she knew that her best friend wouldn't be the same ever again. This would break the detective, and this time there would be no ruggedly handsome author there to help put her back together again.

Kate couldn't hold back her sobs anymore. She sank to her knees and pulled her hands up to her face. Lanie sank down with her, and kept her arms around her friend. They stayed like that for what seemed like hours.

For Kate, the tears never stopped. She didn't think that she would ever be able to stop crying again. Her partner lay nearby on a cold slab, burnt beyond recognition, dead. He had left her. He had promised her always.

The anger that reared up in her was gone as quickly as it had come. But the guilt and regret that followed it couldn't be shoved aside so quickly. She pulled back from Lanie and said, "I wasted so much time, Lanes. We should have been married for years. Years. We should have had children. But I kept pushing him away. He waited for me for years. Waited for me to get my issues in order, for me to finally see that he was the one. I…I…" she trailed off, wiping the tears from her eyes. "I have so many regrets. We should have had all the time in the world, and now he's…gone."

"You listen to me, Kate Beckett, and you listen good. You may have not gotten together when you should have, but that takes nothing, NOTHING, away from the time you did have together. This is not your fault. You hear me?"

"I wish…I wish I could go back and do it all over again, from the moment I met him. I'd do so many things differently. God, Lanie, I treated him so badly for those first four years. At first I hated him. How could I have hated him?"

"You didn't know the real him then, honey. He didn't show you at first. You couldn't have known."

Tears still flowing down her cheeks, Kate nodded, knowing it was the truth. Then something hit her, "God, Lanie, I have to tell Alexis and Martha. How…How am I going to do that? How will I ever look them in the eye?"

Lanie helped her up and said, "You will need each other Kate. Lean on them and let them lean on you. This will be so much easier if you do it together. They'll need you, alright? So don't run away, okay?" She knew her friend had a habit of shutting people out when things got rough. Now was not the time for her to build new walls, not when there were people out there that counted on her.

Again, Kate nodded. She stood on shaky legs and looked again towards the sheet covered body lying on the table across the morgue. "I need to say goodbye." She walked over to it, to him, her legs still weak, tears still flowing down her cheeks, and rested her hands on the cold metal surface. Lanie stood back and let her have some privacy.

"God, Castle, I'm so sorry. I'm going to miss you so much. I don't know how I'll live without you, to tell you the truth. I know you'd be give me a look right now, telling me how strong I am, how extraordinary I am, but I'm not. When I lost my mom, it wasn't strength that kept me going, it was cowardice. I shut myself off from the world, made it so I wouldn't feel anything. That isn't strength. You were the strong one. You made me a better person; brought me out from that place I had had been living in for so long and made me live my life. I'm so sorry I didn't let you in sooner. We could have had so much time together, and I'll always regret that we didn't have the time. That will be my cross to bear.

"I love you. I didn't tell you that often enough. Hell, it took me months to say it back to you after we finally got together. I should have said it sooner. I loved you years ago, Castle, and I will always love you," she sobbed, "please believe that." She took a deep breath and stepped away from the table. "I'm going to be strong for you. I made you a promise that I'd take care of Alexis, and I will do that. I will be strong, and I'll make sure she is as happy as she can be. God knows, I'll never be happy again. I love you, Rick."

She turned from the table, knowing that if she didn't leave soon, she wouldn't be able to force herself away. She turned towards Lanie and said, "Thank you, Lanie. I'm…I'm going to go tell Martha and Alexis. You're right, we should be there together for this."

She gave her friend a hug and walked out of the morgue, not looking back to where her fiancée was lying dead on a slab.

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Telling Alexis and Martha that Rick was dead was the hardest thing she had ever done in her life. She didn't know what to say, or what to do, and when she did finally tell them, it was done through uncontrollable tears and sobs. They hugged one another and cried on the couch in the loft, which felt so empty now that he wasn't there anymore. He'd never be there again. No more sounds of keyboard sounds emanating from the office, no morning coffee and pancakes, no more laser tag battles. He was simply gone, and he was never coming back.

The comforted each other for hours, none of them saying much besides how much they already missed the most important man in their lives. Eventually they decided it was time to at least attempt to get some sleep, knowing that the next day would bring more pain, more heartbreak.

Kate lay in his bed, his pillow pulled to her chest, sobbing uncontrollably. She knew that sleep might never come for her. She knew the minute that her eyes closed she would see that car burning again, would see his burnt corpse slumped against the steering wheel, would see his body lying on the morgue table with a sheet draped over it. The images were already haunting her. She knew in sleep that they would only get worse.

She cried constantly for the next few hours, but eventually exhaustion caused her eye lids to droop. She fought it as much as she could, but eventually sleep took her. Her last thought before unconsciousness claimed her was that she wished she was falling asleep in his arms one more time.

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a/n2- Wow, that was hard to write. Remember that though this starts off with a death, it isn't a death fic in the end. Please review and let me know what you think. The next chapter will be up as soon as I can.