Author's Note: I had never really intended to write a crossover fan fiction, but in honor of the imminent release of Scarecrow and Mrs. King Season Two and the fantastic recent episodes of Castle, I couldn't help myself. Thanks to my friends at the SMK Forum, it became clear that it could work, so here's the result. I'm a bit surprised to see that this looks to be a first of its kind on this site, but excited, too.

This story is obviously AU as I don't think we'll be seeing Lee and Amanda on Castle anytime soon, but I'm trying to stay in character and in canon (for both shows) in all other respects. The general timeframe is present day and starts at the end of Castle 3.16 Setup, so be aware that there may be spoilers for that episode in here. Many little moments from Scarecrow and Mrs. King will pop up throughout this story so I'm not going to list all of them, but where something significant is referenced, I'll try to let you know in that chapter's notes.

Special thanks to Moxie who helped generate wonderful ideas for this story and beta read for me, to mmlarkin who asked some great questions to focus the beginning of this story, to Kauhly who offered a great tip about Lee and Amanda's probable reaction to Fallon and to Petralit who is helping me with a bit of research for later chapters; without them this wouldn't look anything like it does!

Disclaimer: Castle and Scarecrow and Mrs. King as well as their respective characters do not belong to me. I make no money from this, and no copyright infringement is intended. I'm just enjoying some time with a few of my favorite characters and putting them all together in my own little world. The story is mine, however, except where I may directly quote an episode.

Our Future

Chapter One: The Setup

Captain Montgomery sat at his desk, a very concerned Martha Rodgers across from him.

"And how long ago was that?"

"I don't really know, Captain. Two hours, maybe three? You see, Alexis and I were heading for a very exclusive spa when I realized I had left some essentials on my dresser. I could tell when I entered the home that Richard and Kate had been there, her scarf was draped over the couch, but they were gone before we returned. I tried to reach him to let him know of our delay and that we were headed out again, but he didn't answer. I've tried his phone, her phone, her apartment. I didn't want him to worry when we didn't call about the time he expected us to arrive at the resort. Ever since he started working with you all, he's become even more paranoid about my and Alexis' safety than he was before. He would answer just to make sure we were both alright, especially since he knew we'd be travelling. It's not like him to be unreachable for any reason. You have to believe me. I just know something isn't right."

"I do believe you, Mrs. Rodgers. It just helps to have accurate times if we need to establish a search area. Might I ask, though, are you sure they are together?"

"Absolutely."

He steepled his hands and placed them under his chin. "Have you considered that perhaps they are engaged in a—a," he cleared his throat, "personal conversation and don't wish to be disturbed?"

"Richard has feelings for your Detective Beckett, I will acknowledge, but even he, Captain, is far too professional to pursue her while they are working such an important case."

"Case? They aren't working on any case. They were removed by Fallon earlier."

"But that can't be. I saw their— "she fluttered her hands, trying to find the right term, but finally giving up and continuing anyway, "—board contraption thing at the apartment. It's hard to miss a shower curtain strung up across the room. The projector was hooked up to his phone ISB cable, so I assumed they were just looking for something they had missed at the precinct, that they were following up on one of Richard's crazy theories."

He slapped the desktop and rose to his feet. Walking around the desk, he opened his office door and called loudly into the bullpen. "Esposito! My office, now." He turned to Martha and offered her an encouraging smile. "Best to keep this in house until we're sure—Fallon has already threatened charges against Castle. Unfortunately, I'm afraid you're exactly right. They were following one of his wild leads."

Detective Kevin Ryan tapped Fallon on the shoulder as he studied yet another map of the city. "Sir, the team from DHS is here."

"About time. Direct them this way."

Glancing up, he saw Ryan escort two people he had never worked with before. The man appeared to be in sixties somewhere, his hair mostly gray; laugh lines clustered around his eyes and mouth. The woman he guided with a light hand at the small of her back was still beautiful though obviously in the same age range as the man at her side. She carried herself with a peaceful, confident air.

Ryan made brief introductions. "Agent Mark Fallon, this is Lee and Amanda Stetson. Mr. and Mrs. Stetson, Agent Fallon is in charge of this investigation."

The men shook hands, and then Fallon extended his hand to Amanda as well. "A pleasure to meet you both."

He brought them up to speed on where the case stood so far. "Okay, we have a dirty bomb set to detonate and disperse Cobalt-60 somewhere around this city. Our bomb maker is dead but his cousin, Jamal Alhabi, transported said bomb using a truck from his moving company. We found the truck, empty. That's where we are right now. What I need from you is a projection of the most likely places a terrorist would plant a bomb for the most—"

He was interrupted by Captain Montgomery. "We have a problem. I knew that Beckett and Castle left too easily and should have been expecting something like this. They've gone off-grid and are working this case on their own." At Fallon's incredulous look, Montgomery merely smiled and shrugged his shoulders. "What can I say? It's getting to be a bad habit with these two. They don't know when to take a break, even when it comes in the form of an order." He continued, the news getting worse. "But that's not our biggest problem. Mrs. Rodgers says she hasn't heard from or seen them for at least a couple of hours, and they're both unreachable."

"What's the significance, Captain?" interrupted Fallon. "They've both disobeyed orders—it's not surprising that they wouldn't answer their phones."

"Not our calls, I agree. But they'd answer Martha's, or his daughter Alexis' calls. That's why Mrs. Rodgers came here; she's convinced that something's just not right. After I told her that they were kicked off the case," he paused to let that thought sink in, "she let me know about what I can only assume was their copy of the murder board set up in Castle's home."

A woman Montgomery had never seen before spoke up. "Amanda Stetson, Sir. My husband Lee and I have been called in by DHS to consult on this case," she said by way of introduction. "Sir, if I could, I'd like to help find the missing members of your team. Lee is one of the best profilers in the country and I'm just along as window dressing."

She saw her husband smile at her comment and then shake his head. "Amanda, don't you forget anything I ever said? You know I don't see you that way anymore—really, I never did."

Amanda returned his smile, a playful glint in her eyes. "I know, Lee. But I'm really redundant as far as the profiling goes. You have extensive experience with bomb making and deployment strategies, as well as in the profiling department. I'd really like to use my abilities to find their missing detectives."

"Actually, Mrs. Stetson, one of my missing people is a detective, Kate Beckett. Richard Castle is a civilian, a novelist, shadowing her for research." Amanda understood his statement, but was confused by the surreptitious looks and covert eye rolling from the people surrounding him. There's more to this story than the Captain is sharing, she thought.

Some of those gathered were obviously detectives, but one woman stood out from the others. Her age and dress said she was not part of the police force; her worried expression and hand wringing told Amanda that she had to be a mother. She knew from personal experience how to deal with worried mothers.

"All the more reason to allow me to help you," she stated to the group at large. "I began my career as civilian auxiliary years ago. My heart goes out to Mr. Castle. I know what it's like to be out of your element in all of this."

"Any objections, Agent Fallon?" Montgomery queried.

"None, as long as it doesn't compromise my investigation or hinder our finding that bomb in time."

"No one wants the bomb to go off, Fallon." Lee Stetson spoke up, a little angry at the agent's callous disregard of missing members of this team. He had experienced firsthand what it was like to have the higher-ups accept his colleagues, his friends and even his wife at one point, as acceptable casualties. "But neither do we write off law enforcement without at least attempting recovery, regardless of why they are missing."

Amanda interrupted her husband before Fallon could take offense. "Sir, actually, we'll be working on the same thing for a while, albeit in different locations. If we can figure out why Detective Beckett and Mr. Castle felt strongly enough that they disobeyed your orders, we'll find where they went, and maybe the bomb in the process."

She looked lovingly at Lee. "I can remember a few instances where we were off-grid ourselves. It's not an enjoyable experience. I really want to do this." Amanda looked at her husband, who wordlessly nodded his assent to their working separate angles on this one. He knew she was going to mother Mrs. Rodgers, distracting her at the same time she gathered details to find the missing couple. Amanda could do that with anyone, no matter how old they were: teenagers, fellow agents, princesses, and in this case, another mother. She'd even mothered him a time or two. He smiled softly at the memories. It was one of the reasons he had fallen in love with her—she genuinely loved people and would do whatever it took to help someone in distress, whether it was finding a missing person or taking a meatloaf and poppyseed cake to a stranger so she wouldn't go hungry.

Amanda approached Mr. Castle's mother and put her arm around her shoulder. "Mrs. Rodgers, is it? We're not going to let your son and Detective Beckett stay missing very long." She guided her to the murder board. "Does this look like what you found in your son's home?"

Martha looked at the white board carefully. "I can't be certain. I didn't really see anything. It was just a blank shower curtain that he'd left the projector shining on. He can be so thoughtless and flighty sometimes, just leaving things in whatever state they happen to be in when inspiration strikes. I guess that's just his artistic temperament."

"Sir," she again addressed both Captain Montgomery and Agent Fallon, "I think the best place for me to start would be looking at whatever items are left in Mr. Castle's home, seeing if they might have left any notes indicating where they started their investigation. Could you spare a car to drive Mrs. Rodgers and myself there? That is if you've no objections, Mrs. Rodgers."

"Please, call me Martha. If you're going to find my son, we're about to be friends for life. We might as well start using first names now."

"Wonderful. My name is Amanda, and we will find your son and Detective Beckett. I'm sure they've left some clues as to where they went."

Captain Montgomery spoke up. "I can't spare any of my people to help you out—they're all concentrating on locating this bomb. I'll get a uniform to drive you wherever you need to go. They'll know this area much better than you would."

"Thank you, Captain, that would be very helpful." Amanda Stetson stepped to her husband and kissed his cheek. "I'll see you later. Try to stay out of trouble." She looked into his eyes. "I love you."

Lee wrapped his arms around his wife. He had the seniority, both in his profession and in his marriage, to get away with a public display. Both of them had learned early in their marriage that what seemed to be a simple case could be the most deadly. They never parted without an assurance of their love. In this case, there was a dirty bomb involved, so it could be very dangerous for one or both of them before it was all over. In her ear he whispered, "Be careful out there. I love you, too."