Disclaimer: Kirk and Spock belong to Paramount, who'd never let them do this. And since I'm sure they want to do this, they really ought both to thank me... :P
I think I've invented the planet, but if Paramount want that too, they can have it. Unless it's a hellhole with dust storms.
Anyway! On with the story!
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It was a warm summer night on Theta Chi XVII, and Kirk gazed bitterly out across the landscape. He had beamed down with the landing party to survey the planet and stayed in this half-wood, half-plain when his surveys were finished.
Lovely.
Lonely.
It was a beautiful evening. The sun was just beginning to set, colouring the Earthlike blue sky a delicate pink, but the trees and grass still kept their vivid, varied daylight greens. Perfect for what he had always loved to do: sit under a tree and watch the sunset.
Except that the one he was thinking of wasn't here to watch it with him. What made it worse was that Kirk knew that he was down on this planet too. Unless he had beamed back up when he'd finished... and wasn't that just the sort of thing he would do? Kirk flipped open his communicator.
"Kirk to Enterprise."
"Scott here, Cap'n."
"Scotty, has Mr. Spock beamed back up?"
"No, Cap'n. Last time I spoke to him he said he had at least an hour's work left to do. Why?"
"No reason. Kirk out."
And if that didn't stir up speculation among the bridge crew, he reflected wryly, nothing would. Oh well. Let it.
He looked out into the distance, eyes blurring with tears. The sun was setting in earnest now, and he imagined what Spock would look like in this pretty light if he came around that tree now. It would catch his gleaming onyx hair, warm his skin to something approaching Terran normal, emphasise his height and the exquisite grace of his slender body...
It took Kirk a moment to realise that what he saw wasn't a projection of his fantasies but the real, living object of them. Stop drooling, Jim, he scolded himself as the tall Vulcan stopped a metre in front of him, hands behind his back and legs apart in the 'easy' position.
"Mr. Spock," he greeted him. Not inspired, perhaps.
"Captain." Neither, it seemed, was he.
"How's your surveying going?"
"It is finished, Captain."
More silence. Dammit.
"So, what do you think of this planet?"
"It is pleasant, oddly so. It ought to have inhabitants of some kind. Instead, it is empty."
"Spock, do you never stop being the science officer? I wanted something like ' pretty'. Not a dissertation on the lack of people!"
"I am sorry, Captain. Yet it is interesting; life has developed on many much harsher planets than this."
This wasn't the way it was meant to go! "It's a lot like Earth, wouldn't you say?"
"Indeed, save for the lack of people."
Kirk laughed. "You never give up, do you! Okay, it's like Earth without people. Beautiful and unspoilt. All trees and grass and streams. And fabulous sunsets."
"I was not aware that intelligent life has an effect on sunsets, Captain."
"Guess not, "said Kirk, too intent on seeming casual to see Spock's exercise in humour at once and kicking himself when he did, "Come and sit here, there's a marvellous view."
Spock sat next to him, looking out as he did into the sky. Kirk could feel his friend's breathing and the warmth of his body, could have reached out and touched his thigh. He didn't. He waited.
"I came to find you just now, Captain, because I was beginning to experience emotion."
Kirk's heart leapt and he rebuked it, "Really, Spock - you! Well, what was this emotion?"
"When the analysis was finished, the rest of the landing party went to explore and I was left alone. I have often been alone before, but tonight I began to feel... to feel lonely."
Kirk's smile was a little too tight, a little too bitter. "Join the club, Spock. No-one ever likes to be alone on a summer night."
"Captain, that is most illogical. What is unique about a summer night?"
"I don't know why, or what's unique, but summer nights are... special. You need someone to hold. Somebody to love. Someone special to sit under a tree with, and watch the sunset, and talk and kiss until it's too cold any more. Someone..." He stopped when it became apparent that Spock was looking at him with more than his usual interest.
"That was the other... emotion that I felt. Longing. Perhaps even love."
"Me too, Spock. Me too."
They sat in silence for a while, each mind occupied with thoughts and images of their belovèd. After a while, Kirk spoke.
"Spock? Who is it that you feel this for?"
Spock turned his head towards his Captain. Hazel and cocoa eyes met, and there was at last no need for words.