The noise is getting louder. It draws him from the turbo lift along deck 12, walking more slowly now as he targets the source, adapts his scenarios.
For what seems like hours he's prowled the endless empty corridors hunting clues. Visited parts of the Enterprise he hasn't been to since their mission started. He can't remember the last time he enjoyed himself this much. But he's realising he didn't know his best girl as well as he'd thought - and he's identified why she sounds wrong. The starship's mechanics are fine. He's been to the engine room - it all sounds smooth as silk even without Scotty to babysit. What jars is the absence of voices - the loss of human chatter, laughter and movement that are as much a part of life on ship as the whirr of artificial air, the low murmur of warp drive.
But now he can hear an echo of what's been missing. It's irregular - a thump, a hiss, then a double thump. It's not automated. It sounds random. It sounds...human.
He's left this corridor until last. After all it seemed unlikely he'd find his crew hiding out in the gym. But now, as he pauses outside the door, he wonders what he'll find - a fitness fanatic who opted for an extended workout rather than a mass beam out? The terrifying sit ups monster?
He steps quickly inside. Scolds himself for the continuing lightness of mood. This is serious. Star Fleet wouldn't be too impressed to see their golden boy, no closer to solving the empty Enterprise mystery than he was when he woke up, grinning in the dark.
In the dark? Usually the gym lights are on a motion sensor. But he can turn the gloom to his advantage. Cautiously he moves forward, hugging the curve of the wall and keeping a tight grip on the phaser he's picked up just in case. The noise is coming from the far end and he wants to see before he's seen.
Thump... Grunt… thump, thump. Gasp.
He creeps closer. A black shape, getting larger. Suddenly it's huge. Rushing him at speed - hitting him with such force he's off his feet and gasping to reinflate his solar plexus from a prone position before he has time to even think about firing.
He groans, reaching for the weapon that's clattered out of reach. But before he can get to it, he hears another gasp. This time it's unmistakably human, female and... familiar.
"Captain? Captain Kirk? Is that you, sir?"
The lights blink on and he blinks back, trying to focus on the silhouette looming above him, offering a hand.
"Chapel? Nurse Chapel? What the hell?"
"Sorry, sir." Is that a smirk he can see? It's gone before he can be sure. "I didn't mean to…I mean, I didn't realise you were there, here, I mean..."
"As you were, Chapel."
What's that about? Why's he fallen back on parade ground speak?
Trying to reclaim some shred of dignity, he ignores the proffered hand and attempts to leap to his feet with more springiness than he feels. Steps round the leather strike bag that sent him flying. Who would have thought his ship's nurse could pack such a punch?
She's flushed and breathing hard but she doesn't look as exhausted as he'd expect after what appears to be a lengthy session. Various bits of gym equipment are scattered across the mats. She's pulling off her boxing gloves, trying to hide her embarrassment at bowling over her commanding officer
But she's not able to suppress the glint, the sparkle of amusement in her eyes. Blue eyes. Funny that, he doesn't think he's ever noticed the colour of Chapel's eyes before. He clears his throat.
"So... " His voice sounds hoarse. She really winded him. Come on, Kirk. Pull yourself together, man.
"So - Chapel. Report. I mean..."
God, he sounds like the worst kind of command automaton. Tries again. More gently this time.
"What are you doing here? Where's Bones?"
A flicker of annoyance.
"We're not joined at the hip, you know. And what does it look like I'm doing?... Sir."
The 'Sir' is an afterthought. He can see her realise how insubordinate she sounds. She looks down. Swallows. This isn't the Chapel he knows.
That Chapel, the nurse with the strong fingers and soothing voice who's treated him for so many injuries over the years, that Chapel would never have talked back to an officer.
Mind you, he can't imagine 'that Chapel' sweating away her spare time in the gym. And that's some muscle definition she's got going there - biceps, triceps, probably some other ceps under the regulation Star Fleet singlet. And she's done something to her hair. He hasn't seen her for a while - it's quite a transformation.
She's noticed him checking her out. Lifts her chin.
"Sorry, sir. You gave me quite a start. I wasn't expecting anyone..."
"No. Well, you gave me a bit of a shock too." He rubs his midriff ruefully. Decides he won't call her on her attitude. There are more immediate concerns. "I'd like to hear what you're doing here. You do realise you appear to be all I've got left of my crew."
"All you've got left?"
She's confused. Something in her eyes tells him she's not in the loop on this one - not quite with it. Bit like him when he came to this morning. He holds her gaze. He needs some answers now.
"Yes, Chapel. You're it... Your crewmates have all gone AWOL. Think. Just how long have you been working out in here? How did you get to the gym?"
She reacts to his shift in tone. Seems to recognise the steeliness although he hasn't raised his voice.
"Er... I... I'm not really sure when I came in, sir."
She pauses. Frowns. "I don't remember." He watches her engage her brain, think back,. It doesn't take her long to figure out what's missing. "Actually I don't remember how I got here either. Do you think...?"
She's running the scenarios. He recognises the signs. She's working through her own checklist, discarding theories, extrapolating. A less experienced crew-member would have had at least a moment of panic right about now. But Chapel lost her rookie status a long time ago.
"I need my tricorder."
He can see she's arrived at the drug/noxious substance theory he had as number one on his alternatives list. She's starting for the door - all business now, embarrassment seemingly forgotten. Then she turns back. There's that glint again.
"You mean we're really the only ones on board? I wondered why I had the machines all to myself for so long." The grin is an echo of the one he had on the bridge. She's already caught up - living in the moment and ignoring the darker possibilities.
Suddenly he's glad she's the one who's ended up sharing this slightly surreal experience with him. Spock would have been great at curbing his wilder theories - running his inbuilt logic software through the facts. McCoy - well, McCoy would have had them both on biobeds from the start - and leached away the joy of his empty Enterprise with his grumbles about the lack of staff. But Chapel - now this could be fun...