Author's Note: Apologies for not being able to post last week but RL got in the way and I'm afraid I have to apologize in advance as I don't think I'll be able to post next week either since I'll be travelling. After that, I'll be able to resume my usual posting schedule, I promise!

The Best-Laid Plans

Chapter 16

They found Aaron Determan in his office, dictating instructions to a woman who Kate assumed was his secretary. "... and call the decorators to come by first thing tomorrow to take a look at the new office. I want it to be ready for me to move in by the end of the week. And then call up–"

Kate knocked on the open door to get his attention and he clipped, "Can't you see I'm in the middle of something?" before he belatedly looked up and she flashed her badge.

"Detective Kate Beckett, NYPD. Sorry to interrupt," she added, insincerely. "I'll try not to take up too much of your time."

He didn't look pleased but he could hardly refuse. "Oh, yes, Detective. I understand. I was told to expect police to be asking about Ben. Please, come in."

He turned to his secretary, flashing her a quick smile. "We'll pick this up later, Eve. Get started on what I was just talking to you about."

"Yes, of course, Mr. Determan," Eve gave him a small smile and then left the office.

"Now, how can I help you, Detective?" Determan returned his attention to Kate, entirely sober and with a shade of impatience in his tone.

"This is Rick Castle, who consults with the Department," she noted, glancing at Castle to see him turning back around to face Determan as he appeared to have been watching Eve leave. She felt a quick little twist of something before she realized that the look on his face wasn't admiring, had nothing to do with attraction. Instead, he looked pensive, a faint frown on his face, a look she recognized from when he was trying to put pieces together about a case, and she wondered what he'd noticed or thought he'd noticed.

She turned back to Determan. "We just need to ask you a few questions about Mr. Wardlow. I believe you'll be taking over as CFO now that Wardlow is dead?"

"Well, I am the Deputy CFO so it's the natural progression."

"Of course," she murmured. "How would you describe your relationship with Wardlow? Did you like him?"

He sat back in his chair. "I didn't dislike him, if that's what you're asking. We were colleagues, we've worked together for years."

"I've heard from a couple of people that you and Mr. Wardlow argued often."

"They were friendly disagreements between colleagues. Don't you ever disagree with your colleagues?"

She did, of course, but then her colleagues also didn't end up dead under suspicious circumstances. She didn't say that aloud. "Then you were not, for example, eager to take Wardlow's place as the CFO?"

For the first time, some real emotion, a touch of anger, flashed across his face. "Yes, I wanted to be CFO, it's what I've been working towards my entire career. But did I kill him in order to get promoted? No, I didn't."

"Can you tell me where you were last night between around 9 p.m. and midnight?"

"I was at home, working. I had a conference call with our Asia office from 9:30 to 11:30 and then after that, I finished up some more work and then went to bed."

"Thank you. Would you mind giving us the names and contact information of some of the people who can confirm you were on the conference call?"

"Eve can give you that information. Eve!" he raised his voice a little.

"Yes, Mr. Determan?" Eve appeared in the doorway almost immediately.

"Print out a list of the calendar invite for the conference call with the Asia office for the detective, will you? Thanks, Eve." He flashed his secretary a smile that he removed pointedly the moment he turned his attention back to Kate. "Is there anything else?"

"What about your predecessor, the former Deputy CFO?" Castle interjected.

She moved her foot to nudge his in the closest thing she could manage to kicking him so Determan wouldn't notice.

"What about him? He's dead."

"Rather convenient for you, wasn't it? Another sudden death that allowed you to be promoted," Castle observed, ignoring a second nudge from her foot.

Determan stood up. "I had nothing to do with that, whatever you're implying. And now I think we're done here."

Kate perforce had to stand up too, mostly because there wasn't much more she could ask and certainly he wasn't about to cooperate further even if there was. She handed him her card and told him to contact her if he thought of anything but doubted, even while saying it, that he would.

Eve was waiting for them with a print-out of the notation on Determan's calendar which included a list of the other attendees along with their email addresses.

"Thank you, Eve," Kate gave the woman a polite smile. "Can I assume you will be moving to what used to be Marissa's desk now that Mr. Determan will be the CFO?"

"I know Mr. Determan's ways," she explained. "That's generally the way things are done around here."

"So I've heard."

"I'm sure Mr. Determan would be lost without you," Castle chimed in. "Do you like working here?"

"Of course," she answered immediately. "If you'll excuse me, I have some things to take care of for Mr. Determan."

Kate handed Eve her card too and then she and Castle left.

"Castle, what–" she began.

"I know," he cut her off. "I pushed too hard in asking Determan about his predecessor so directly."

His admitting it so freely took all the wind out of her sails. "Why'd you do it?" He knew better than that by now.

He grimaced. "He just annoyed me. So… arrogant and self-righteous."

"So he wasn't winning any points on charm," she conceded. "But that doesn't make him guilty. He does seem to have an alibi."

"A conference call?" he scoffed. "How do we know he didn't just dial into the call, say hi, and then leave to go kill the victim and come back?"

She made a small face. "It seems a little improbable but I admit it's at least theoretically possible. Which is why the first thing I'm going to do when we get back to the precinct is email the other people on the call and find out."

"Of course you will," he responded, looking more cheerful. "So, did you find out about the guy who threatened the victim?"

She gave him a brief summary of what she'd seen in the victim's work emails, which included the irate email from Dustin Marconi, adding that the boys were going to bring him in, and then told him what Marissa had told her about the victim.

He nodded but there was a small frown on his face.

"What?"

He made a small face. "Just thinking that killing someone and making it look like an accidental overdose is not a crime of passion so this Dustin Marconi would have to be very clever and cold-blooded to make such a plan in the heat of anger, as it were."

"Maybe that's why it took him this long to act on his threat," she reasoned but admitted it seemed rather unlikely. In her experience, people who were angry enough to send threatening emails were not the kind to then sit calmly down and make a detailed plan to get revenge and for that matter, someone who was smart enough to make such a plan to commit murder was unlikely to have also been stupid enough to send an email announcing their intentions so plainly.

"I suppose."

"But it doesn't seem likely to me either," she conceded.

"So Determan is still our best suspect," he countered eagerly.

She shot him a small smile. "You really didn't like him, did you?"

"How can you tell?" he joked.

"Keen detective insight," she returned dryly. "Since you're practically waving a sign around saying you don't like him."

"Oh, admit it, you didn't like him much either."

"No, I didn't," she agreed, "but unlike you, I'm not quite as ready to lock him up and throw away the key just based on that fact."

"I don't think he's guilty because I don't like him; I think he's guilty because he has the best motive!"

"In your entirely unbiased judgment," she drawled.

He scowled at her and she had to laugh.

They had arrived back at the precinct by then so this discussion of sorts of Determan's guilt or lack of it was necessarily tabled. The boys were out tracking down Dustin Marconi so she let Castle update the murder board while she briefed the Captain on what they had learned so far.

The calendar invite for the conference call Determan claimed to have been on during the time of death listed 11 attendees, aside from Determan, and she picked three of them at random and sent them emails asking them to confirm Determan's presence on the call, although it occurred to her that since they appeared to all be in the Asia office, she probably couldn't expect a response until tomorrow morning.

The boys brought in Dustin Marconi for questioning but Kate soon had the impression that Marconi wasn't a strong suspect. The boys reported that he'd appeared to be genuinely shocked at the news that Wardlow was dead and he was candid enough not to pretend much sorrow over the fact. In her experience, murderers usually went out of their way to deny any problems with the victim, crocodile tears and all. She could tell just from Castle's expression, his stance, that he didn't think Marconi was guilty either.

But she asked for Marconi's whereabouts the night before, as a matter of rote, and he answered that he and his wife had been out to dinner with friends, which had ended around 9:30, and then they'd returned home shortly after 10. It was a soft alibi, of sorts, and she sent the boys out to confirm it while she and Castle got to work going through the victim's phone records and financials, looking for any red flags.

This was always the tedious part of a case, like looking for a needle in a very big haystack without even knowing if a needle was actually there to be found or what the needle looked like. But at the same time, it didn't seem particularly so to her because Castle was there, supplying her with coffee and snacks and occasionally making facetious comments to break up the monotony.

She felt a little flare of alarm when she realized this, just how much she'd already come to rely on his presence, and hurriedly told Castle he could head home.

He looked surprised, as well he might since the afternoon was only half over. "You sure?"

"Go on. You have a book to finish and you know you hate the paperwork part of a case."

"Well…" he hesitated.

"Besides," she hurriedly added, "I don't want to be responsible for your murder when your publisher kills you for being so late with your book."

That made him crack a smile. "Your concern for my welfare is touching, Detective."

"I'm just trying to avoid the hassle. It's pure self-interest," she quipped.

He smirked. "If you put it like that, I guess it would be mean of me to resist. So I'll see you tomorrow."

"Night, Castle."

He left and she tried not to notice, or think, that his absence made the whole task of going through the victim's phone records seem even more dreary than it had been. Never mind, she was perfectly capable of doing her job without Castle there.

Which might have been true but she still couldn't help her smile the next morning when Castle arrived and she couldn't even convince her own self that the smile was more about the coffee he brought than it was about the man carrying the coffee.

"Morning, Beckett. Any news on the case?"

She set her coffee down, schooling her expression into sobriety. "Actually, there is. I hate to start off your day with bad news but it turns out you were wrong. Aaron Determan's alibi is solid so there's no way he killed Wardlow."

"I take it the other people on the conference call got back to you?"

"Yes, and they confirmed that not only was Determan on the call but he was one of the people who spoke the most."

"Oh, damn, another tragedy!"

"A tragedy, Castle, really?"

"It's something I read somewhere. A tragedy is a good theory defeated by a fact."

Well, that explained it. "By that definition, you endure a lot of tragedies with every case we work on," she teased.

Castle made a face at her. "Yes, yes, rub it in, why don't you?"

"But actually, I was thinking, what if there's a reason that Determan's alibi is so solid?"

He brightened. "You mean, a conspiracy."

"Exactly. He is still the one with the best motive. And the boys went back and talked to the victim's other neighbor and confirmed that they didn't have any visitors that evening so it looks like the killer is a woman which got me thinking. What if we're looking at a Lady Macbeth situation? Determan is married, remember."

Castle straightened up, his expression changing in a way she recognized. "No, I don't think it's the wife, I think it's Eve."

She blinked. "Eve, his secretary? Killing someone because your boss told you to is a little extreme."

He waved a hand. "I don't think she did it because he's her boss; I think she did it because she's in love with him."

"She's–what? Wait, is that what you noticed, when you were watching her walk out of Determan's office yesterday?"

He leaned forward. "Yes. He smiled at her, remember, when he dismissed her and I could see it in her face."

She didn't doubt Castle's word. He was observant and good at reading people. "So you think they're in it together, then?"

"It makes sense, doesn't it? She certainly would have known where Wardlow lived and Wardlow would have easily trusted her, let her in. She probably brought some work papers with her and told him he needed to review them, distracting him so she could drug his wine and then wait for him to pass out. And of course they'd plan it for an evening when Determan has a solid alibi. If Determan is half as clever as he thinks he is, he would have wanted a back-up plan assuming the overdose story didn't go through."

She sat up, a jolt of excitement shooting through her as she remembered something. "Oh and I just remembered, in looking into the background of everyone we talked to, Eve has a sister who works at a hospital so she would have access to morphine!"

Castle grinned at her, not just a look of excitement over a new lead on a case.

"What?"

"Oh, just thinking that this is why we make a good team. I come up with a theory and you find evidence to back it up."

"It's not actual evidence, just another possibility," she cautioned.

He made a face at her. "Thank you, Detective Spoilsport. But the theory is solid. She supplied the means and opportunity and he has the motive. It all fits."

"You're right, it does fit. And we already know the killer has to be smart because not every killer could come up with a plan that was so close to being ruled an accidental death, almost certainly would have been if only Wardlow hadn't been a friend of the Mayor."

"You mean, if the Mayor hadn't wanted you to look into it," Castle corrected with a small smile.

She fought back a blush, which was easy enough considering her next thought. "This is a great theory but you realize, we have no proof. The neighbor only saw the woman's back and that's not going to be enough to make a positive ID that any court will buy and so far, Ryan hasn't found any useful traffic cam footage."

He slumped and sat back. "This needing-actual-evidence thing is a pain."

She gave him a faint smile. "Welcome to life as a cop. We're not allowed to just make up evidence…" she sobered, straightening up. "Unless…"

He jolted upright, frowning. "Beckett? I know you're not about to suggest falsifying evidence so what are you planning?"

"We're not allowed to make up evidence but we are allowed to bluff about the evidence we have in order to get a confession," she pointed out.

"You think we can bluff Determan into confessing?"

"No, not Determan–Eve. She's the weaker link, I'm sure of it. And she loves him so she'll want to protect him."

He smiled. "You're very sneaky, even conniving sometimes, you know that?" His tone and his expression made the words a compliment.

"Needs must," she returned. "You on board?"

"I think we should bring Espo and Ryan with us, extra show of force," was Castle's response.

She grinned. "Espo will get a kick out of looking threatening."

They went over to talk to the boys, who agreed, Ryan with a touch of hesitation but Ryan was the most cautious poker player of all of them, to say nothing of the most straight-edge cop she'd ever met.

The arrival of all four of them at the office building caused a bit of a stir and for once, Kate decided it was a good thing, would play into the intimidation thing.

Somewhat irritatingly, now that she had two male cops with her, Determan didn't betray even a little impatience when they appeared and requested more of his time and he didn't demur when she said Eve should also be present.

"Yes, Detectives, what can I do for you?" Determan asked.

She ignored him and focused on Eve, while Espo and Ryan took up their places, Espo taking up a forbidding stance beside Determan but facing Eve, while Ryan and Castle ranged themselves on either side of Eve so she was surrounded. Kate saw the widening of her eyes, the nervousness she tried to hide, and knew she had the woman.

"Eve, we wanted to know why you never mentioned your visit to Wardlow's home the night that he died," Kate began, letting her voice harden as she went on. "It seems like pertinent information, don't you think? Instead, we were left to find out from a witness, one of the neighbors, who saw you when you were leaving and has identified you. Better come clean with us now or it'll only go worse for you."

"What? Eve, what are they talking about?" Determan blurted out and Kate glanced at him to see that he looked stunned. Was he just that good of an actor?

She caught Castle's glance at Determan and then at her before Castle shifted and turned to face Eve. "I get it," he addressed Eve, his voice sliding into his sympathetic, story-telling voice, the voice that could probably beguile any woman. "You did it for him, didn't you? He persuaded you, didn't he, told you it was fool-proof and you'd never get caught? And you just wanted to help him, make him happy. That was all you wanted, wasn't it?"

Kate pinned her eyes on Determan, who was just gaping and looked horrified. "What'd you promise her, that you'd divorce your wife and marry her if she did it? Did you enjoy that, creating a murderer and getting so close to getting away with it? Nice try, but conspiracy to commit murder is just as illegal and I'm sure you'll do fine in prison–"

"No!" Eve burst out and they all turned to stare at her. She was pale and clenching her hands together. "No, he didn't know anything! It was me!"

"It's too late to lie to protect him, Eve," Castle said, his voice still sympathetic. He had inherited more acting ability from Martha than he admitted.

"No, I'm not! He didn't know! It was all me!" she gulped. "I did it–my sister–she's a nurse at a hospital–that's how I got the morphine."

"Oh my god," Determan burst out. "Oh my god, Eve, what are you saying? You–you killed–" he broke off, his voice almost cracking. Kate felt her certainty in his involvement wavering. "How could you do that?" He fell back in his chair, covering his face with his hand. "Take her away. Take her away now! I can't even look at her–"

"I did it for you!" Eve was crying now. "I wanted you to be happy, wanted you to have everything you wanted! You said, you told me that being a CFO was all you'd been working towards, what you wanted most!"

Kate nodded slightly and Ryan took her signal, pulling Eve to her feet, gently enough, before he handcuffed her. "Eve Coxton, you are under arrest for the murder of Ben Wardlow…"

Ryan recited her rights and Espo joined him as the two of them escorted Eve out to their car.

Kate felt abruptly tired. Sometimes, it seemed as if solving a case was as dispiriting as when they were stuck. What a life, what a job, this was, constantly having to witness the worst in people.

Castle had moved and she felt a quick, fleeting touch on her shoulder, which provided an odd measure of comfort. "We'll leave you now, Mr. Determan," she managed. She couldn't apologize for accusing him of murder; it was her job and they'd had good reason for suspecting him. Plus it didn't change the fact that she still didn't particularly like him, but at the same time, it was hard not to feel a little sorry for him, looking as shell-shocked as he did.

He lowered his hand to look at her. "I swear to you, I had no idea. I never imagined…" His voice trailed off, trembling slightly. "I would never have wanted something like that to happen to Ben, not even for the job."

He looked so shaken that she believed him. Certainly, he wasn't the type of man to show such weakness easily so she couldn't believe it was feigned.

"Eve made her own choice," was all she said. It would have been too strange to wish him a good rest of the day or anything so she only added, "Goodbye, Mr. Determan."

And then she and Castle walked out of the building, ignoring the people who gaped at them, no doubt having witnessed Eve being taken away.

"Well," Castle sighed as he sat back in her car, "I wasn't expecting that. To be right and wrong all at the same time. We're really quite something."

She managed a faint smile. "I guess so. Sorry; I know you wanted Determan to be guilty."

He waved a dismissive hand. "Well, maybe it's for the best. I was thinking that this might end up being a good thing in the long run, teach him a modicum of humility. I don't think he'll be quite so cut-throat in his ambition after this and probably not as arrogant either."

Trust Castle to find a silver lining. She felt amazingly comforted by it too, that the fact of a murder might push a person to change, become better. "You might be right." She paused and then added, "Nice job in there, by the way, getting Eve to crack."

He slanted a small smile at her. "We make a pretty good team."

"I suppose we do, Hooch."

This made him laugh outright and she grinned at him, feeling her spirits lifting.

"But just so you know, I do not consent to that being my new nickname," he pretended to grumble.

"I don't remember asking for your permission."

He threw her a mock scowl and she smirked at him. (And not for the first time, she wondered how she had gotten through her work without falling into depression or something like that before he had come along, brightening her work life with his quips and his silliness, even as it could be irritating at times?)

Back at the precinct, she found that the boys had already started processing Eve's arrest, leaving her to update the Captain, who could then call up the Mayor, while she called Mrs. Wardlow and was able to tell her that her husband's killer had been arrested. Never an easy conversation but easier than telling someone about a murder in the first place and as she reminded herself, it helped to have answers, know the reason.

Afterwards, she got started on the paperwork to close the case, aware that she needed to be particularly thorough in this one, thanks to the Mayor's interest in the case.

Castle took down the murder board and afterwards, wandered over to chat with the boys.

She glanced up at them at the sound of Ryan's laugh, seeing Castle's answering grin, and had just turned back to her paperwork when her phone rang. "Beckett."

"Detective, hi," a voice that sounded vaguely familiar responded, "this is Mark Vogle from Briggs Morris. We met the other day."

"Oh, yes, of course. Hello, Mr. Vogle." She made a small face, not pleased as it appeared he must have deliberately asked someone, possibly Marissa, for her number just for his own purpose. She inwardly grimaced. She wasn't even flattered because she wasn't at all interested. (She couldn't imagine being interested in another man at all. At least not yet. Not ever, a little voice in her mind corrected, not in a world where Castle existed.) She cut off the thought. No, no, she could not believe that was true.

"I heard you found out who killed Ben and wanted to congratulate you on solving the case. I was wondering if you'd let me take you out for a drink because I'd love to hear all about how you solved the case."

Oh bother, her guess had been right. "Thank you but no. I'm actually seeing someone," she lied. It irritated her but she knew that claiming to be seeing someone was the quickest way to get a man to back off from his pursuit, as if only being claimed by another man was a valid reason for a rejection. And she already knew just from meeting him once that Vogle was one of those overly-confident types who would not easily accept a rejection and she didn't want to deal with attempts to persuade her to change her mind.

"Oh, that's my loss, then. You know where to find me if that ever changes."

"Yes, well, I really should get back to work. Goodbye, Mr. Vogle," was all she said before hanging up, grimacing at the phone.

She had barely turned her attention back to her paperwork when she became aware of Castle's presence by her desk and glanced up at him.

"Did you just say you were seeing someone?" he asked without preamble.

She blinked, surprised. She had tried to pitch her voice lower than usual just because of the subject matter so how had he even heard her from over by the boys' desks? "Oh, that was a lie just to avoid a date. It seemed the quickest way to get rid of him."

"Oh. Oh right." He paused and glanced away, seeming distracted by something across the bullpen, before going on, "I was actually thinking I might head out for the day since the case is closed. Finish the book, you know."

"Oh, sure," she managed, feeling an absurd dip in her spirits. "That's not a problem. Just the paperwork left after all. Go and write."

"Yeah," he agreed, turning back to her. "Night."

"See you tomorrow?" she blurted out as he turned away, before she'd fully realized she was going to.

His steps momentarily paused. "If I can finish the book," he answered. "See you later, Beckett."

With that, he left and it wasn't until he was in the elevator and out of sight that she belatedly realized that he hadn't met her eyes and had there been a flicker of something like… disappointment or worse in his expression, his tone, when she'd told him about the lie? Oh. Oh, wait. Had he–could he have thought that she'd been referring to him when she said she was seeing someone? It would make sense considering, well, everything. Castle was the closest she had actually gotten to seeing anyone in a while, since Demming hardly counted considering they'd only shared one brief, lackluster kiss. And Castle was certainly the only man she was interested in seeing, at least at the moment.

But she'd been so focused on her own thoughts, her own fears, that she hadn't really stopped to wonder, or at least not for long, if Castle might think differently, might want more. She winced a little. She'd been myopic and self-centered but, well, now she knew. She supposed it was time she and Castle actually talked about this… thing… that had happened, if only for her to be clear, let him down gently. (She had to let him down, didn't she?) She inwardly winced at the thought. She didn't want to hurt him but better to tell him, be up front now, so he could get over the sting.

Just… not quite yet. She wanted more time to get her own thoughts in order, figure out what to say since this sort of conversation was not her strong suit. She could allow herself that much, couldn't she?

And now she was procrastinating. Which she tried not to do, at least not when it came to work, but her personal life was another matter, as usual. Oh, bother…

~To be continued…~

A/N 2: Full disclosure, the crux of the plot in this case is from an episode of the show "Elementary," as I came up with a blank on trying to think of another case idea on my own. And again apologies for not being able to post next week. I'll try to post the next chapter as soon as I can so you won't need to wait a full two weeks.