A/N: My first dabble into the Whoniverse! This is based on the line from the episode "42," where the Doctor promises to take Martha ice-skating on the mineral lakes of Koorharn. Enjoy!

After spending forty-two achingly-long minutes this close to the surface of a livid, living sun who tried to possess her best friend and secret crush, it was hard for Martha not to get excited about going somewhere nice and cold. And the Doctor had made a point that he absolutely did not want to talk about what had happened on the cargo ship, so that was really a dead end. Perhaps he would want to talk about the ordeal later, after he had had time to process it, or perhaps they wouldn't speak of it ever again, but right now he was determined to travel to Koorharn—wherever that was—and take her ice-skating.

And the idea was terribly tempting.

"When was the last time you went ice-skating, Martha, m'dear?" the Doctor asked, throwing levers and pressing buttons.

Drifting around the console until she stood behind him, she chewed her lip. "Um… not since I was a kid, I guess." She tilted her head. "What about you?"

He glanced at her briefly before tapping his fingers against a screen—entering coordinates for the mysterious icy planet, maybe? "Once, I think. At the Rockefeller Center the day it opened."

"When was that?"

He exhaled noisily through his nose. "Oh, 1936 or so." He slapped the screen with his palm. "Might be a bit rusty." She shook her head and watched him casually flutter around the console like an errant bee, shushing the little whisper inside asking who he took with him.

And then they were off.

The TARDIS, grinding noisily, sloshed them around like ice in a glass before sliding gently onto something solid, hopefully land. The Doctor then ushered her into her room, shouting to bundle up as he knotted a long colored scarf around his neck and pulled on a pair of gloves. As he slipped into his long coat, she dug a wooly parka out of her wardrobe and shrugged it on before tugging a knitted hat down over her ears. They grinned daftly at each other as he handed her a pair of ice skates.

"Ready?" he asked, slinging the skates over his shoulder.

Pulling on a pair of mittens, she nodded brightly. "Always, Doctor."

Still grinning at her, he strode toward the door and flung it open, inviting a brisk wind to sweep inside. He sucked in a deep breath and stepped out, Martha right on his heels.

"Oh… oh my God," she breathed, gazing out the doorway, too stunned to move forward. Silvery, glittering snow blanketed the smooth landscape in every direction, the incredible whiteness broken only by the few copses of spindly black trees stretching their long fingers toward the lavender sky. A hundred feet from the TARDIS's open doors was an enormous blue lake, shimmering like a gigantic mirror beneath the radiant sunlight.

The Doctor's voice broke her out of her reverie. "You coming, Martha?" He was standing a few feet away, ankle-deep in fluffy whiteness, staring at her curiously.

"Yeah, of course," she said, stepping to the ground and listening to the snow crunch pleasantly beneath her boots. "It's just so… so beautiful!"

"Innit, though?" Smiling, the Doctor offered her his hand and they picked their way across the tundra. "Can you believe it's actually summertime?"

Martha stared blankly at him. "No."

He nodded. "That's why there's no one here."

That blue, blue water gently slapping the shore seemed a little less inviting as images of choking in wet darkness drifted through her mind. "But… but it's water."

By this time they had reached the shoreline and the Doctor dropped her hand rather unceremoniously to yank off his trainers. "Yep," he said, tying the laces together and depositing them under a forlorn-looking bench.

"You can't skate on water, Doctor." Nevertheless, Martha realized rather belatedly she had sunk to the bench, one boot already off and an ice skate in her hand.

"Right, right, you'll just sink right through." Whipping out his sonic screwdriver, the Doctor aimed the blue beam at the blades on his feet until they crackled with energy. Waving his hand in a "gimme" motion, she gingerly lifted her legs to the bench and he grasped each ankle in turn, beaming her own skates. "There. All better!" Hopping up, he turned away to clomp toward the glistening waves.

Wondering for perhaps the eightieth time that day about the Doctor's mental stability, Martha clambered to her feet and tottered through the snow after him. He stood on the edge of the lake, practically bouncing in his skates, while he waited for her. Clasping her mittened hand tightly in his, he peeked at her out of the corner of his eye, the corner of his mouth curling upward. "First step's a doozy," he said, then practically tore her arm from its socket as he dragged her into the water.

Except it wasn't water. When the blades on their skates came into contact with the lake's wavy surface, the water instantly froze solid. Instead of being drenched to her knees like she had expected, she and the Doctor were skittering across a thick sheet of ice.

Digging in her heels, Martha pulled tight on the Doctor's arm until he was yanked to a halt beside her. "What the hell?" she squeaked, her knees buckling in shock as she clung to his sleeve. "How is it doing that?"

Looping his elbow through hers, the Doctor helped straighten her wobbly legs and pointed down at the faintly humming blades. "Mineral lakes never freeze," he began, "so the Koorharns invented special ice skates that, when magnetized on the proper frequency, are powerful enough to draw up all the minerals floating around in order to form a solid surface sturdy enough to hold them."

"Are you sure it's safe?" she whispered, still unconvinced. "It's not going to spontaneously melt or anything, is it?"

"Well, Koorharns weigh about fifty stone on average," he explained, "and you and I are just tiny little things in comparison. Besides, it's solid all the way through. See?" He tapped the ice forcefully with the toe of his blade; it didn't even chip. "Perfectly safe."

"You sure?"

He sighed exasperatedly. "Martha Jones, have I ever put you in danger?"

Bending down, she poked the liquid water's rippling surface inches from her feet with her mitten. "Not intentionally…"

"There, you see? Now, come on!" With a strength she never expected existed in such a skinny frame, the Doctor hauled Martha back to her feet and took off across the ice, leaving sparkling twin paths in their wake.

Gradually, as reason slowly reasserted itself and she didn't plunge beneath the waves, Martha stopped screaming bloody murder and started squealing with delight. Eventually she found the courage to let go of the Doctor's arm and go careening off in another direction. She twirled and leaped, sketched figure eights and carved her name in glass. She chased after the vermillion fish darting through the sapphire water, laughing when they flipped into the air and flopped down again, swimming close enough that she could catch one in her cupped hands but always just beyond her magnetized skates.

When the Doctor circled back, she reached for his hands, coaxing him into spinning in frenzied spirals. They threw their heads back and laughed loudly and hysterically, causing the nearby trees to shiver and quake. And when they slowed and Martha could barely see straight, her skate nicked a blemish and with a shriek she fell, taking the Doctor down with her. Lying side by side on the ice, breathless, groaning in pain—which swiftly transformed into yet another bout of giggles—Martha closed her eyes.

And quickly opened them again when she heard what sounded like a sob.

Turning her head in alarm, Martha saw the Doctor bite his lip as a glistening tear streamed down the side of his face. The medical student within her demanded she check for injuries—what if he had hurt himself when they fell?—but she didn't want to startle him with an unwanted touch. So instead she quietly asked, "Doctor, are you all right?"

It seemed ages before she heard his voice again, and when she did it was soft and brittle. "I was so scared, Martha."

Ohh… Martha rolled to her side. "It's over now," she said gently. "We're on this beautiful planet and we're alive and safe and it's all thanks to you."

Shaking his head feebly, he whispered, "I… I could've killed you."

"No," she said firmly, reaching for his hand and squeezing tightly. "I know you would never hurt me, Doctor."

After a moment of tense silence, he tilted his head toward her. "No, you don't," he murmured.

Even though Martha knew he was over 900 years old, she had always found it difficult to reconcile the fact with his rather youthful appearance, which didn't seem so far distant from her own. But now, staring into his deep brown eyes, she finally understood. Pain and wisdom and more sorrow than she had or ever would experience in her life stared steadily back, and she was surprised at how ancient and world-weary his eyes were, set completely at odds with his thirty-something face. Especially when there were still tears leaking from his eyes.

Sweeping back his spikey bangs to dab at the tearstains with her mitten, she smiled slightly. "Yes, I do."

They laid in silence, Martha gently rubbing his cheeks and the Doctor simply staring back at her. Finally, when his face was dry, the Doctor took her free hand and kissed it for a long, lingering moment. "Have I told you lately," he whispered, stroking the back of her hand with his gloved thumb, "how thankful I am I brought you onboard?"

"No." Her eyes dipped shyly. "But it's always nice to hear."

Smiling broadly, he slid forward and pressed his cool, bluish lips to her forehead. "Thank you, Martha Jones," he said.