Disclaimer: The wording is mine but the characters aren't.

I think I know where I'm going with this fic now, but I'm thinking of a break until there is more interest. The last chapter was difficult to write and 4 reviews was a little disheartening (I know that's selfish).

Thanks to those who have left reviews, they're really encouraging.

Are you following?

…..

Leaving the small man behind, she ran past the rest of the staff at the desk and the few people waiting in the chairs until she could see the far end of the ward. The curtains were still drawn back but the only person she could see was a nurse with an armful of new linens who had paused in surprise to watch Beckett's abrupt arrival.

"Where are they?" she demanded. The nurse looked flustered, looking around for support.

"They?" the doctor caught up to her.

"Where are they?" she snapped at the nurse again, her breath barely squeezing through the panic crushing her chest.

"Mr. Donovan?" the young woman stammered. "He and his brother?"

Kate just stared at her.

"They left about ten minutes ago."

…

9.

"Who takes their car when they're only going a few blocks?" Esposito slid the transmission into drive with impatient force.

"She needed a place to wait until Beckett got home?" The sound of their seatbelts clicking off were synchronized.

With Beckett's apartment being in a largely residential part of town, there were very few security cameras. It had taken a lot of time and patience from both of the doormen on her building to get a description of a car that was frequently seen parked on the same block. A dark navy sedan, a Japanese import. It seemed neither of the two men were very good at remembering the names. A Hyundai or a Honda. Hell, it might have even been a Toyota.

They did notice the woman sitting in the car twice though.

Louise Prenton.

Didn't they know Beckett's last apartment went up in smoke? They really should be warned to pay attention to loiterers. Knowing the trouble Beckett and Castle attracted, there was a chance this wouldn't be the last time.

Serial killers, snipers, stalkers…

"This just doesn't seem right," Esposito shook his head, sliding smoothly from the sedan and ushering the door closed with a crisp snap.

Ryan glanced at him across the roof in the evening air outside the same apartment building for the second time today.

"Stalkers are happy to stay hidden," Esposito tried to reason. "They just watch until they're ready to make a move."

"Maybe this is her move?" Ryan suggested uneasily.

"What?" Esposito couldn't keep the frustrated edge out of his voice. ""What is her move?"

"I don't know. She wanted to see Beckett last night."

"So where the hell is she now?"

"She wants Beckett to come and find her?" Ryan hazarded, obviously channeling Castle.

It wasn't a bad theory and it gave him something to argue; helped him to clarify why he thought it was wrong: what he thought was the right answer. Is this how Beckett worked?

Beckett. He was not going to let this become another Dunn case.

"She's clean," Esposito grumbled. "How does she just disappear and then come back to knock Donovan around?" That took planning, connections or training. Louise Prenton was a veritable girl scout. He doubted they were teaching girl scouts how to disappear, and if they were, that should probably be addressed.

"I don't blame her," Ryan muttered, joining his partner and making for the lights of Louise Prenton's lobby. He had been off balance since going through the photos, obviously creeped out on Beckett's behalf.

"Wish we could get a warrant to check out his place, too. The guy's a nut job."

"Agreed," Ryan flashed his badge at the evening doorman.

The apartment was all in order with no signs of a struggle, though Esposito doubted the CSU technicians had extended their services to housecleaning. There was just obviously not much to find- the dude got hit with a pan; not exactly the blood he was used to as a homicide detective.

"CSU report said fire escape hasn't been touched," Ryan offered, coming back into the main room from the bedroom, camera in hand.

"Anything else?" Esposito asked.

"I got nothing. No other photos. No Nikki Heat. I checked all the drawers and the closet too."

What kind of stalker this pronounced, had a place that clean and free of indicators? It just wasn't right.

"I'm telling you, bro, this is wrong."

.

"We would just appreciate it if you could give us a call if you see her," Ryan tried to placate the evening doorman; he wasn't nearly as affable as his daytime counterpart.

"When was the last time you saw Ms Prenton?" Esposito tried again.

The man gave a sharp nod and a small smile to a resident who brushed past them before he answered, "I saw Ms. Prenton last night. She and Mr. Donovan went out about 10."

"And what time did she leave this morning?" Ryan had his notebook out.

"I didn't see her this morning."

The two detectives shared a look. "When we talked to your colleague this afternoon, he said he hadn't seen her since yesterday."

"Then she must not have come back yet," the doorman sighed.

"Yet?" Esposito pressed.

"Sure," the man answered, responding to the urgency in the detective's voice with a slightly quicker answer. "I didn't see her come home last night after they left at 10."

"But Donovan was in her apartment at noon. He said he saw her off this morning," Ryan insisted.

The two detectives froze at Ryan's phrasing.

"Yes. They left together, but Mr. Donovan drove the car back alone; I guess he stayed the night."

"What time was that?"

The man squinted a little, trying to recall. "It must have been around 11.30."

"After Louise tried to get in to see Beckett," Ryan dropped his head back and squeezed his eyes shut.

"Sir, where is that car?" Esposito asked.

…

It felt wrong and somewhat perverted, but Castle listened intently after the bathroom stall shut. He didn't extend the same courtesy to his other senses however, keeping his breathing even through his mouth. While it wasn't the first time he had paid attention in a bathroom, in fact he got a surprising number of details there- tattoos often showed up in fascinating places, he had never followed a man into the bathroom. Women? That was another story – one he had to make sure Kate never found out.

If his alert system wasn't trilling as insistently, he would not be here.

He heard a thin tinkle and almost shook his head. Thomas Donovan didn't need a cubicle, he just had size issues.

Didn't he want to see how he measured up to the man he was impersonating?

Castle set aside the bedpan on the sink that tucked itself in against two walls in the corner of the room and pulled out his phone. There was no message from Kate yet, but that was merely a matter of time.

It didn't take a bestselling author to image what her reaction might be if she got back to find both of them gone with no clues. Her mental health won out over the threat of bodily harm and he typed out a single word text before Donovan emerged from his hideaway.

Toilet.

He pursed his lips and added 4th floor as he heard the toilet flush. He sent it quickly and opened up Angry Birds to explain the device in his hands. He admittedly was a little transparent in his exaggerated facial expressions and shaking the phone, making up for the lack of sound, but if his suspicions were correct, Donovan wasn't really a genius.

The man in question glared at him in the mirror as he soaped his hands diligently. Castle knew the expression was probably more likely to be due to personal animosity rather than suspicion regardless of the fact that acting seemed to have skipped him. But he was cautious in placing himself in the path of the exit as casually as he was able, pocketing the device without regard to his high score.

When he profiled people, one of the parties was usually restrained. He preferred it when it wasn't him. So this casual setting was new to him. How do you profile someone who would run?

Castle lamented not having a badge; at least that way Donovan couldn't file assault charges if it came down to physical intervention.

From the level of dedication Donovan was showing his soapy hands, he was more than officious enough to try anyway.

Obsessive.

"Stop staring," Donovan said shortly, meeting Castle's eyes in the mirror, breaking the silence he had kept since they left the treatment ward,.

"I spent a lot of time with a pathologist a few years back," Castle confided, figuring this was the most isolated and safest place to start, especially with Kate on the way. He could hold this narrow doorway. "You know, for research. Now, not that I'm an expert, but when I look at your face- it looks to me like you just smacked into a wall," Castle squinted and then corrected himself, certainty rising. "Actually, not a wall. I'm thinking a door or a doorjamb," his face was hard, inspired by the edge of the door frame uncomfortably digging into is shoulder. "From the side, by the looks of things. I understand why you wouldn't go at it head-on; nose injuries are surprisingly painful and it's hard to un-break a crooked nose."

"What?" Donovan slowly shut off the water.

"You caught the side of your mouth too though, didn't you? It's swollen," Castle pointed out. "Fry pans have quite the diameter, just like a bedpan. If you were hit by something like that, your cheek bone, mouth and your nose should be blue right now."

Donovan tensed at the accusations, his mouth thinning.

"Well?" Castle asked. "If it's true, you might want to avoid filing those charges, no doctor who sees the photos is going to buy your fry pan story."

"So maybe I walked into the door." Donovan offered tersely. "Maybe I thought if everyone thought she attacked me, you would lock her away. Do you know what it's like to be with someone like her? She's completely insane!" Donovan paused what was quickly becoming an outburst for air and Castle considered telling him he didn't know crazy until he lived with Meredith. "Why do you think I have to dress like this?" Donovan continued, plucking at the plain white T-shirt, leaving water prints behind.

Castle nodded sympathetically and saw the other man relax marginally. "That was quite well done," Castle complimented him. "Especially for improv: very convincing. My mother would be impressed."

Donovan's face went carefully blank. "I don't know what you mean."

"I've also seen more than my fair share of the obsessive. We both know Louise doesn't fit into that category, but I'm sure Kristie has already told Beckett that by now. "

"Who?" Donovan's face was black.

"Kristie O'Sullivan," Castle repeated. "That was who you were talking about back at your bed, wasn't it? Beckett doesn't forget."

The crash that followed that statement was unexpected.

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