Spock decided, in his own definition, that it was 'necessary to reciprocate gratitude.' His solution took precedence over sleep, when he finally returned to his own cabin.
He took his stack of attempted cards to a replicating machine, and tore them into precise strips.
The color would not be correct, nor would the texture. He recalled an earth saying of which the captain was fond: it's the thought that counts.
Spock had thought about this. More than once, and backed it with research and a sleepless night. That, he felt, would 'count.'
Kirk spun in his chair on the bridge, glancing quickly between Spock and Uhura's stations.
"Lieutenant," he decided, "Call for Mister Spock, and have him report here immediately."
"Aye, Sir."
"I don't think he's ever been late," Kirk continued, face wrinkled with worry, "Ever."
"I'm sure he has a good reason," McCoy said, from his post behind the chair, "And he knows you'll forgive him."
Swiftly, Uhura altered switches and dials on her console.
"He's not in his quarters, Sir," she said, holding her earpiece, "Shall I switch to the intercom?"
As Kirk dismissively waved his hand, he noticed a fleck of grey, slowly settling on the floor. He glanced up, and saw others following from the vents above.
Doctor McCoy studied Kirk, first, before deciding to follow his gaze. Kirk's hand was drawn to his side, and folded blankly over the armrest. Several specks collected in the creases on his uniform.
He nodded.
"Intercom should do it, Lieutenant. Call for Scotty, too."
"Yes, Captain. Switching to intercom now."
A light flashed on the panel of the captain's chair.
"Engineering to Captain Kirk."
"Kirk here, Scotty. Are you on your way to the Bridge?"
"I will be, Captain, once I get the air vents figured out."
The captain watched the sprinkling of grey, as it proceeded. Uhura brushed the debris form her hair, and sent a wave of it fluttering from her station, with a steady breath. Most settled again on the desk, leaving watery trails behind them.
"I think we may be having the same problem," Kirk said slowly, "Do what you can."
"Aye, Sir," Scotty said, "Y'know I will."
"Is it… dangerous?"
"That depends what it is, Captain, but it's not blocking the airflow and that's all I'm concerned with."
"Alright, Scotty, thank you. Kirk out."
He sat and stared straight forward; the viewing screen did not indicate anything unusual. Mister Sulu verified that they were still on their course to the starbase.
"Theories?" the captain presented to all of his officers, with waiting hands.
Spock emerged from the lift, nodding once at Uhura before stepping up to his station. He picked up a sample of the grey paper and rubbed it between his fingers.
"Now, if you just call that 'fascinating,'" McCoy began, "I'll—"
"Gentlemen," Spock said, as Kirk prepared to repeat his question directly, "I had hoped the human concept of 'imagination' would present this to you as snow. I see now that my theory, Captain, was incorrect."
Kirk's smile was thin and thoughtful.
"Snow?"
Lieutenant Uhura giggled, and cupped some of the false snow between both hands, marveling at the cold sensation.
"I've never seen snow!" she exclaimed, "Is it real, Mister Spock?"
Chekov was unconcerned with the answer, and immediately prepared a snowball, which he displayed tauntingly before Sulu.
"It is real in that it exists," Spock recited, "But it is not pure water."
"I wish you would've given me a warning, Mister Spock," Kirk presented, playfully, "I think I've got Scotty worried half to death."
"From what I understand, Captain, it is not customary to reveal the identities of gifts, prior to their reception."
"Well," McCoy said, folding his arms, "A gift from a Vulcan?"
"That is what the current situation would suggest, Doctor."
Kirk stood and paced around the perimeter of the room, watching the childish delight as it spread between crewmen.
"Not all of Earth sees snow, Mister Spock," he said lightly, stopping at Uhura's station. She was attempting to copy Chekov's flawless snowballs, but was much slower, and let it melt between her fingers. Fragments of the paper remained behind, forming a soggy glove.
Once the captain returned his focus to Uhura, McCoy nudged Spock's shoulder. The Vulcan turned to face him, as he held up a handful of snow.
"I hope these aren't all your Christmas cards," he said.
"Replicated versions, Doctor."
"Then you didn't tear up the real ones?"
"The human dependency on the word 'real', Doctor, is fatiguing. It was necessary to tear the original cards before beginning the replication process."
"But you need one to send home, Spock," he dropped the wad of paper, and wiped his hands together, "I'm not letting you off this ship without one."
"As you are well aware, I do not require shore leave."
"I'll send it for you," he said, "I promise."
Spock nodded, trapped in agreement, as the captain turned to rejoin them.
"A… thoughtful gift, Spock. It'll be hard for the rest of us to follow."
"When've you got it scheduled to switch off?" McCoy asked.
The captain chuckled.
Well it doesn't show signs of stopping,
And I've brought some corn for popping.
The lights are turned way down low,
Let it snow! Let it snow! Let it snow!