Thanks to TimeLord98 for beta reading!

For about a half an hour, Jim and Spock pushed through thick ferns, thorn bushes and tangled webs of vines before they discovered a clearing in the dense jungle. In said clearing was a small pool. They decided to gather some readings and other things for the science team to analyze.

While Spock was crouched over the water with his tricorder, Jim took a moment to listen to the alien bird calls in the 300-foot trees and the sound of water flowing down a wall of rocks and into the pool below. This planet was pretty nice. It would have been perfect if the average temperature weren't 39 degrees centigrade. The heat caused Jim to sweat right through his shirt, and his hair began to stick to his forehead. He looked like he'd just taken a shower with his clothes still on.

Spock stepped away from the pool, put away his tricorder, and stood in his usual position: back straight and hands behind his back. Unlike the captain, Spock didn't look like a mussed up cat. His uniform was pristine as usual, his hair didn't have a strand out of place, and he wasn't even breaking a sweat. He grew up on a desert planet. He was used to it. But it wasn't as if the weather didn't have an effect on him.

If they weren't on duty right now, the Vulcan would have taken off his science blue uniform and finished this away-mission bare chested. He had recently begun to acclimate to the cooler temperatures of the Enterprise, and now he was starting to see why Jim couldn't spend more than five minutes in his quarters without having to take a trip to sickbay for heat exhaustion. After the third time, the good doctor used his superior powers as CMO and banned Jim from Spock's quarters.

"Captain, I have completed my analysis of the water and taken samples in order for the rest of the science team to 'take a closer look,'" Spock explained. "The water contains abnormally high concentrations of stroenzenite and aikomium.

Jim deflated a little bit. His plan to cool down had failed before it even started. "So it's dangerous?" he asked.

"Negative. Stroenzenite and aikomium are minerals found in this star system. They are completely harmless and are essential in the survival of some species. The humanoid reptile species that resides on Terileptus, the Terileptils, absorb this mineral through their skin..." Spock was about to start rambling on and on about the minerals' medical uses, unique chemical properties, and this and that. Normally, Jim would just leave him be, because although Spock would never admit it, Jim could see how excited the Vulcan got about all that science-y stuff. But now was not the time for that.

Jim was hot. He was too hot. He needed to feel that water hug his body, and the sound of it running down those rocks made it worse.

"...found in deposits near the planet's surface. Stroenzenite also becomes fluorescent when exposed to certain pollutants, which is why it is highly valued in the-"

"Jim abruptly cut off Spock's monologue. "So even with high amounts of these minerals, the water's safe for general consumption?"

"Yes, but-" Spock's explanation was cut short once again, as he was faced with a rather...odd question from his captain.

"What about skinny dipping?" he asked. His first officer's reaction elicited a wide grin from Jim.

"Captain," Spock said, "I would advise against going 'skinny dipping' at this moment."

Jim simply ignored the Vulcan and proceeded to strip off his clothes. He pulled his shirt over his head, causing his wet hair to stick up all over the place. "I'm the captain, so I'm going to do it," he stated defiantly. Once his shirt was off, he took off his boots, and all at once, removed his pants, underwear, and socks. He sighed deeply and spread out his arms when he was finally free of the restrictive clothing, then gave Spock a quick wink before cannonballing into the water with a 'splash!' The impact made a huge chunk of the water spray in Spock's general direction; causing him to jump back.

Jim stayed submerged for a few seconds, letting the wonderful coolness envelop him before he came up to the surface only to see a rather smug looking Vulcan in front of him. The human part of Spock wanted to burst out in a fit of laughter, but he forced it back down into the recesses of his mind.

Jim scrunched up his eyebrows in confusion. "What?" he asked. When he didn't get an answer right away, Jim just knew something was up, and pointed an accusing finger at Spock. "Spock, what did you do?"

"I have done nothing, Captain," The utter and illogical amusement tried to push its way back out again. This time, Spock let some of it trickle through. "However," he continued, "I believe that it is my duty as your first officer, and friend, that I tell you that you are blue."

Jim looked down at himself and let out a high-pitched scream that made the birds in the trees screech and fly away in alarm. He was blue. He was fucking blue from head to toe. Jim pulled a lock of his hair down in front of his face, and sighed in relief that his blond hair wasn't tainted along with the rest of his body.

"Actually, Captain, your skin tone is much closer to shade of blue once known as 'TARDIS blue' by avid fans of the 20th and 21st century British science fiction show Doctor Who," Spock oh-so-helpfully supplied.

Jim grated his teeth against each other as if he were trying to sharpen them, and curled his hands into tight balls underneath the water.

"If you would have allowed me to finish my explanation," Spock continued, "then I would have been able to inform you that stroenzenite and aikomium, when dissolved into a solvent together, causes the solvent to become a highly concentrated natural blue dye. This particular body of water, as I previously stated, contains extremely high amounts of both these minerals, which is why when you came into contact with it, your skin was dyed blue."

The captain's left eye began twitching, like it did when he got really pissed. If he weren't so blue right now, his face would look like a fire truck.

"I...what is that phrase that humans use?" He furrowed his brow in concentration. "…'told you so,'" he said with a now obvious upwards turn of his lips. Spock looked quite pleased with himself.

"You 'told me so?' You 'told me so?!' You didn't fucking tell me anything, Spock! All you did was ramble on and on about lizards and glow-in-the dark rocks! Now, because of you, I look like a fucking blueberry!" Jim was going to march right out of that pool and-and dammit! Every single scenario he could think of seemed to end with him leading Spock back to the water and having epic water sex. For now, he went with folding his arms and contorting his face in such a way that it looked like he was trying to shoot imaginary lasers through Spock's head.

Spock's face, on the other hand, relaxed to its normal, expressionless state. "Jim, I suggest that you calm yourself."

Calm himself? Calm himself? That pointy-eared bastard! He was the youngest starship captain in Starfleet history and he was fucking blue! How the hell was he supposed to calm down?!

It was right at that moment when Sulu and Chekov decided to break through the thick growth. "Keptin?" Chekov's voice rose an octave; he looked like a deer in headlights. His friend was frozen in place, his own eyes darting back and forth between Spock, Captain Kirk's uniform, strewn across a rock, and the captain himself: very naked and very blue.

Spock turned around and casually acknowledged the gawking ensign and lieutenant. "Mr. Chekov. Mr. Sulu." He nodded his head at both of them. "I believe that we are finished here. The two of you and Ensign Tyler may beam back up."

Chekov, still petrified, replied in an almost hypnotic way, "Ensign Tyler was eaten by a monster, sir." He wanted to tear his eyes away, but seeing the captain blue…it was just so mesmerizing.

"I see. Please go back to the Enterprise and inform Doctor McCoy of the captain's...condition." There was that smirk again. So subtle, yet so obvious. Spock was enjoying this a bit too much.

"Huh? Oh," Sulu shook himself out of his stupor, a slight flush creeping up the back of his neck. "Sorry, sir. Chekov!" He snapped his fingers in front of the Russian's face, making him jump back to reality.

Sulu simply shook his head and straightened out his uniform, then pulled out his communicator. "Enterprise, two to beam up."

"The two friends disappeared in a shimmer of light, leaving Spock and his now blue-skinned companion alone again. "I suggest you replace your clothing, Captain," Spock teased, "You would not want to further your embarrassment by reappearing on your own starship both blue and naked, now would you?"

Jim grumbled 'stupid Vulcan' to himself as he climbed out of the pool. He snatched up his clothes, which ended up looking like someone smeared blue paint all over them by the time he finished putting them back on. At least he wasn't hot anymore.

"Enterprise, two to beam up," Jim barked into his communicator.

"The captain sounded pretty angry. The man in charge of the transporters spent no time hesitating to bring Jim and Spock back on board.