The place was old, decrepit, abandoned, and would probably have been torn down years ago if it wasn't for the efforts of the 'Save the Embarcadero' action committee. They had lobbied for decades that the old hotel, once in a high class part of the city and now surrounded by fashionable tenements and custom workshops, should be restored, used as low cost housing instead of being boarded up so not a crack of light could enter, a blight and eyesore on the landscape. Most of all they wanted the grand ballroom – once the heart of the building where the rich, famous and downright notorious used to dance the night away – brought back to its former glory for use as a conference hall, community centre ... whatever worked.

What didn't work was the body in the middle of the parquet floor.

"Well?" Kate Beckett asked, looking down at the man in the tuxedo lying on his side, his knees drawn up towards his chest.

Lanie Parish made another note on her pad, her face lit by the bare bulbs hanging from the ceiling. "No blood, no evidence of blunt force trauma, bullet or knife wounds, strangulation ..." She shrugged.

"So it's a natural death?" Rick Castle sounded disappointed.

"When uniforms arrived they said the dust was all churned up, but, from the footprints they could make out, it was only our victim." Lanie pointed down with her pen towards the man's shoes, scuffed and dirty, and the bottom six inches of his pants which were coated with grey. "Apparently it looked like he'd been running in circles."

"Walking." Rick had gone down onto his heels and was studying a line of impressions in the thick layer covering the floor. "His weight's evenly distributed. If he'd been running it would all have been on his toes, and we wouldn't see evidence of his heels." He stood up. "Like the Hound of the Baskervilles."

She squinted at him. "What?"

Kate rolled her eyes a little. "It's how Sherlock Holmes knows the late Lord Baskerville was running for his life in the snow."

Rick grinned, only a little smug. "I knew I was a good influence on you."

"I read it at school, Castle." She looked back at her friend. "Any ID?"

Lanie glanced at the two men waiting just a few feet away. "I gave it to ... them."

Javier Esposito gave his erstwhile girlfriend a slight smile, but the frosty look he got in return made him shudder a little. He lifted his notebook like a shield, reading conspicuously from it. "Roman Sobranksi. Forty-eight, lives on the west side, and owns the Embarcadero."

"That Sobranski?" Kate was surprised. "I thought he was a recluse."

"No, just sick." Kevin Ryan had stepped closer. "I spoke to his housekeeper, a Mrs Kepple, and between the sobs I got that he had heart problems and was under doctor's orders to stay in bed and avoid any undue stress. Only there's a City Council meeting tonight, and Mr Sobranski here was intending to put his case for tearing the whole place down and build condos."

"That would be criminal," Rick said. "There's history in these walls." He indicated the peeling fragments of yellow silk wallpaper and the frames where mirrors once reflected hundreds of couples. "If only they could talk ..."

"Anyway," Esposito said, a little louder than necessary, "a surveyor was supposed to come yesterday to check things over, only he ran late so he turned up this morning instead, and found the doors wide open, no sign of forced entry, and Mr Sobranski lying here." He sneezed. "Sorry," he added quickly. "It's the dust."

Kate nodded slowly, her gaze on the body. "So if he had a history of heart disease ..."

"There's a bluish tinge to his lips," Lanie said. "I can't give you a definite cause of death until I've got him on the slab, but my prelim is heart attack. Probably between 10 and midnight last night."

"Hallowe'en," Rick commented, then almost took a step back as all eyes turned to him. "What?"

"Are you suggesting ghosts did this?" Kate asked.

"No." He held up both hands. "Just ... saying."

"And you don't have to remind us," Ryan said, grimacing slightly. "I only just got rid of the headache."

"Ah, my special brew." Rick smiled. "I did warn you."

"I don't know about this place being condemned," Esposito said, "but your parties should be."

"What did you come as again?" Ryan wanted to know, vaguely remembering something about a long brown coat and suspenders before he'd had one too many of the purple concoction.

"Can we get back to the body in hand?" Kate interrupted, feeling more than a little fragile herself, despite the morning rapidly turning into afternoon.

Rick grinned at her. "You looked lovely, by the way."

"So you said. Several times." She deliberately turned her back so she couldn't see the smirk on his face. "So it's natural?" she asked the ME.

"No signs of foul play." Lanie signalled the two techs waiting to collect the body. "Unless I find evidence of a hypo mark, or tetrodotoxin in his system, I'd say this wasn't a homicide."

"Fine."

Within ten minutes Mr Sobranski had been taken away to keep his appointment with Lanie's scalpel, and Ryan and Esposito had followed, bickering gently about something and nothing.

Rick gazed fondly after them. "Do you think they're ever going to stop arguing?"

"Who?"

"Esposito and Lanie."

"They're not arguing. They're ... on a break." Kate was checking her voice messages on her cellphone.

"Well, they need to chill out." He caught himself. "Actually, no. Last night at the party I almost got frostbite asking Lanie what was going on."

Kate shook her head, keeping the smile at bay. "I told you not to say anything."

"I thought I could help."

"This from the man who's been married twice and has so many notches on his bedpost I'm surprised you don't sleep in a heap of matchwood."

"Nice."

"Oh, come on, Castle. You're not really the one to talk about relationships."

"Maybe not. But that doesn't mean I wouldn't be happy to give advice."

"Lanie would eat you alive."

He chuckled. "That could be fun too." He went back to studying the walls. "You know, I bet this place looked amazing once."

"I imagine it did."

"My mother says she remembers dancing here back in the day, probably not long before it went downhill. According to her it was like something out of a fairytale. The chandeliers, the mirrors, the smell of the candles ..."

"You make it sound like she was here in the 19th century."

"Maybe not that long ago. But it was some charity ball, before I was born."

Kate's eyes lit with mischief. "Maybe this is where she met your father."

His jaw dropped. "I hadn't thought of that."

"They danced the night away, and as the sun came up they went up to his room, hand in hand, sipping champagne and making ... whoopee."

"Whoopee?"

She grinned. "Or something. And ended up making you."

He shuddered theatrically. "That's just ... eww."

"It's natural."

"Not thinking about your parents doing ... that sort of thing." He grimaced then looked around. "It would be a shame if they demolished it, though. All those stories that would be lost." He glanced back at her. "You know, it's said that Eduardo Viducci planned his campaign against Carlo Gambini in one of the booths at the back. Before he ended up sleeping with the fishes, of course."

"Not thinking about buying it too, are you?" she asked. "This isn't like The Old Haunt. It would take more than just a few bucks to put it all back together."

"No," he admitted. "It's just ... you know ..."

She had to smile at the wistful look on his face. "I know."

"I mean, you can imagine it, can't you? All the women in their jewels, sparkling brighter than miniature suns. And the men in their dinner jackets, polished and primed for action." He swept his arm towards one end of the ballroom. "The orchestra is up there, on the platform, filling the air with music amid the thousand and one perfumes fighting for dominance." He held out his hand. "Shall we?"

"What?"

"Can't you hear it, Kate? Just there, on the edge of nothing. Listen, Kate. Can you hear it?" He started to sway, just a little, his eyes half closing as if to take it in better.

"No, Castle. I can't hear anything. There's nothing to hear."

"One two three, one two three … Let go, Kate. Just … let … go." He reached out and took her hand, pulling her into his embrace, and as reluctant as she was she only fought him for a moment, finally allowing him to lead her down the room.

She was lightness itself in his arms, and he knew he should be surprised that she could dance like this, but she surprised him every day, so to worry about it was pointless. Instead he reveled in her closeness, the scent of cherries coming to him on her personal warmth, the glow on her cheeks that was for him alone.

Around and around, the dust lifting from beneath their feet to swirl in eddies as they passed between phantom dancers, music neither could hear urging them on faster and faster, twirling and dipping and twisting and … until they came to a sudden stop, both panting slightly, gazing into each other's eyes.

He knew what he had to do, wanted so badly to do, just to reach down those couple of inches and press his lips onto hers, to remind her of what he felt, what he knew she felt too …

She let go and the spell was broken. Stepping back she coughed. "Sorry," she murmured. "Dust."

"Yes." He wanted to follow her but didn't, instead saying, "You know, maybe that's what he did."

"Who?"

"Sobranski. He knew he was going to ask for permission to tear the place down, so maybe he came here for a last dance with the ghosts."

She raised an eyebrow at him, back to being Kate Beckett. "So now you are saying it was ghosts that did it."

"No. Not … really." He backpedalled, but his mouth kept going. "Just that maybe he had an imagination and did what we did, and danced with someone who wasn't there, and his heart gave out."

"Really." Her phone buzzed and she pulled it from her pocket. "Beckett." She listened for a moment, then nodded. "We'll be right there." She thumbed the off switch and looked up at him.

He swallowed, tasting dust on his tongue. "Another body dropped?"

"Literally. Damian Colby's on the sidewalk outside the Colby building, and someone says they heard an argument just before he fell from his office on the twenty-third floor."

"Or was pushed?" Twenty-three floors … murder or an accident, either way, it was going to be messy.

"Perlmutter's there already. I'm sure he'll tell us."

"You know he likes you, don't you?"

If anything her eyebrow went higher, then she turned on her four-inch heel and stalked out.

For a long moment Rick stood still, simply surveying the ballroom. When they left the power would be turned back off, and the shadows would crowd back in, filling the space with soft blackness. It was a shame, but with Sobranski dead he'd probably get his last wish, and the hotel would be torn down. Nobody had the money to spend on it, and the most anyone could hope for was that it would molder quietly away, decaying gently until someone made a decision somewhere, and the wrecking balls would move in.

He sighed. It really wasn't fair.

Something touched his cheek and he brushed at it. Probably a cobweb from the ceiling, disturbed by all the traffic below, and not the spectral hand his writer's imagination insisted on. Still, maybe there was a certain rhythm to the sound of the city outside, and all it would take was for him to close his eyes to see the dancers reflected in mirrors that broke long ago, to hear the music drifting on the still air, to feel a palm pressed to his as he waltzed into oblivion …

"Castle?" It was Kate, standing in the doorway. "Are you coming?"

"Yes." He shook himself. "Yes. Coming. Right now." Wiping at his face once more he followed his partner out into the life of the city.

A moment later the lights died as the power went off, yet in that one nanosecond before the glow was gone the music swelled behind them, and the shades of what once was danced back into the shadows of forever …